The Conversation – Page 272 – MIL Submissions Engine

March 19, 2026

Dans le Var, la progression de la cochenille-tortue du pin menace les paysages méditerranéens

Source: The Conversation – France (in French) – By Romain Garrouste, Chercheur à l’Institut de systématique, évolution, biodiversité (ISYEB), Muséum national d’histoire naturelle (MNHN)

Deux femelles adultes de _Toumeyella parvicornis_ fixées sur une tige de pin maritime protégées par une fourmi (_Crematogaster scutellaris_), à Grimaud dans le massif des Maures, en octobre 2023. Romain Garrouste, Fourni par l’auteur

Le département du Var, en France, est touché par l’arrivée de cet insecte venu d’Amérique du Nord qui s’attaque au pin maritime et au pin parasol. Si la cochenille-tortue du pin se propage, elle pourrait transformer durablement les paysages et l’écologie du pourtour méditerranéen.

Des terrasses qui collent, des voitures poisseuses… On croirait d’abord à une histoire de pollution, puis on lève la tête vers les pins parasols caractéristiques du littoral méditerranéen. On voit alors leurs aiguilles noircir, leurs silhouettes familières se dégarnir, leurs grosses branches dépérir puis se rompre.

Derrière ces symptômes constatés dans le Var se cache un minuscule insecte, qui prend une place gigantesque dans les préoccupations locales : la cochenille-tortue du pin (Toumeyella parvicornis). Venue d’Amérique du Nord, on l’a détectée pour la première fois en France en 2021 dans le golfe de Saint-Tropez, dans le Var – un département en première ligne pour les espèces exotiques.

Discrètes, célèbres ou redoutées

Mais qu’est-ce donc qu’une cochenille ? Insectes de l’ordre des hémiptères, apparentés aux pucerons, aux cigales ou encore aux punaises, elles se caractérisent par une biologie souvent discrète. Les femelles adultes sont peu mobiles et restent fixées sur la plante hôte pour se nourrir de sève, tandis que les rares mâles sont souvent de petite taille, ailés, et d’une courte durée de vie.

Beaucoup d’espèces portent une cuticule épaissie ou cireuse, parfois en forme de petit bouclier – d’où l’impression de petite écaille collée au rameau. Certaines cochenilles sont célèbres pour un usage ancien comme colorant – la cochenille du carmin, par exemple. D’autres sont redoutées en agriculture, en horticulture et en foresterie, car elles peuvent pulluler, affaiblir les plantes et favoriser des champignons par l’intermédiaire du miellat qu’elles produisent.

Il y a plus de soixante ans, le massif des Maures dans le Var avait déjà vu arriver une cochenille, Matsucoccus feytaudi. Alors qu’on ne lui connaît pas de dégâts notoires en région atlantique dont elle est endémique (Landes en France, Espagne, Portugal, etc.), elle a détruit dans ce massif 120 000 hectares de pins maritimes en vingt ans de présence.

Biologie et mécanismes de dégâts de la cochenille-tortue du pin

Mais venons-en à celle qui nous intéresse, la cochenille-tortue du pin. Originaire d’Amérique du Nord, Toumeyella parvicornis appartient à la famille des Coccidae.

Elle se fixe volontiers sur les jeunes rameaux de pins, perce les tissus végétaux et se nourrit directement de la sève. Ce vol de ressources affaiblit l’arbre, mais le mécanisme le plus visible est ailleurs : l’insecte rejette en quantité un miellat sucré qui rend tout collant, attire souvent les fourmis… et, surtout, nourrit la fumagine, un champignon noirâtre qui recouvre aiguilles et rameaux, y compris les strates inférieures.

gros plan sur une colonie de cochenilles sur une branche — Colonie de *Toumeyella parvicornis* avec femelles adultes et petites larves fixées (rougeâtres), à Grimaud dans le massif des Maures, octobre 2023.
Romain Garrouste, Fourni par l’auteur

Résultat : la photosynthèse est freinée et empêchée, l’arbre s’épuise, il perd des aiguilles et voit sa croissance stoppée. Des infestations fortes et répétées peuvent mener jusqu’au dépérissement et à la mort de l’arbre, souvent précédés de chutes de branches qui rendent les abords dangereux.

La France prudente après l’expérience italienne

Comme beaucoup d’espèces exotiques, les raisons de la diffusion de la cochenille tient à un « alignement des planètes » défavorable : augmentation des échanges commerciaux de végétaux et de matériels, densité d’hôtes (plantations notamment) et hivers plus doux.

En France, les foyers actuellement identifiés se concentrent encore dans le Var, mais un premier cas a été relevé à Martigues, dans les Bouches-du-Rhône. Les impacts visibles ont été identifiés sur le pin parasol (Pinus pinea) et le pin maritime (Pinus pinaster).

Face à ce constat, les autorités sanitaires ont mis en place une surveillance et des recommandations de gestion : un repérage précoce, des précautions lors des travaux d’élagage, une limitation des déplacements de végétaux potentiellement infestés, et le signalement des symptômes.

Les dégâts restent encore relativement localisés à l’échelle nationale, mais l’expérience antérieure de l’Italie nous invite à la prudence. La cochenille-tortue du pin a été signalée dès 2014 en Campanie, dans la région de Naples, avant de gagner d’autres régions jusqu’à atteindre Rome, où le pin parasol constitue une icône paysagère et culturelle.

Les infestations ont entraîné des dépérissements massifs, et les gestionnaires ont dû intervenir sur des arbres adultes, parfois patrimoniaux. Plusieurs études récentes utilisant des indicateurs de croissance, des mesures physiologiques et de la télédétection ont pu mettre en évidence les liens entre l’intensité de l’attaque à la baisse de vitalité des pins et au risque de mortalité en Italie.

Après l’Italie et la France, l’espèce a aussi été signalée dans d’autres pays du bassin (par exemple, dans les Balkans), ce qui alimente la crainte d’une diffusion à l’échelle méditerranéenne, d’autant que le pin parasol est présent sur une large partie du pourtour méditerranéen.

Une menace écologique majeure

Le point crucial, souvent sous-estimé dans le débat public, tient au rôle du pin parasol et du pin maritime. Loin d’être de simples arbres d’ornement urbain, ils structurent les milieux naturels, parfois au cœur d’aires protégées.

Dans la réserve naturelle nationale de la plaine des Maures (Var), les pins parasols participent à des paysages uniques et à la structuration écologique locale. Ils façonnent une ambiance de plaine ouverte arborée très caractéristique.

La disparition ou le dépérissement de ces arbres n’aurait pas seulement un effet esthétique : elle affecterait la structure du milieu, les microclimats locaux et toute une biodiversité associée aux pins – faune, champignons, cortèges d’invertébrés, etc. Une grande partie du littoral du Var fait partie de l’aire du parc national de Port-Cros, directement menacée par cet insecte.

Le pin maritime, comme le pin parasol, dépasse en outre largement le cadre méditerranéen. Il est présent également sur la façade atlantique, où il constitue l’essence dominante du massif landais et l’un des plus vastes ensembles forestiers d’Europe occidentale. Une extension de la cochenille-tortue vers ces régions – si elle s’y acclimatait et y trouvait les conditions propices – poserait donc des questions écologiques, paysagères et économiques à une tout autre échelle : santé des forêts, gestion sylvicole, risque d’affaiblissement face aux sécheresses et coûts de surveillance.

Plus largement, ce cas illustre comment un insecte de quelques millimètres peut, en interaction avec la mondialisation des échanges et le changement climatique, devenir un facteur de transformation durable des paysages et des écosystèmes, en s’associant aux modifications en cours, en modifiant l’identité visuelle et écologique de régions entières. L’enjeu dépasse donc la seule nuisance : il interroge notre capacité à anticiper et gérer les invasions biologiques avant qu’elles ne redessinent, silencieusement, nos horizons.

La cochenille-tortue des pins (Toumeyella parvicornis, Coccidae, Hemiptera). Source : Ysyeb/YouTube.

Des pistes de solutions au cas par cas

Face à cette invasion, les solutions restent jusqu’ici limitées, surtout sur de grands arbres. Il n’existe pas de « recette miracle » universelle. La gestion implique une approche intégrée, qui combine détection précoce, réduction des sources de dispersion, tailles ciblées quand c’est possible et maintien de la vitalité des arbres : arrosage raisonné en période sèche, protection des racines en contexte urbain, limitation des blessures.

paysage d’arbre rompu par les dégâts causés par un insecte — Dégâts de *Toumeyella parvicornis* sur pin parasol, défoliation et chute de branches, à Grimaud dans le massif des Maures, en octobre 2023.
Romain Garrouste, Fourni par l’auteur

Des pistes existent aussi du côté des ennemis naturels de ces insectes. Comme pour d’autres cochenilles, certains prédateurs, notamment des coccinelles, peuvent consommer des cochenilles jeunes, et des communes testent parfois des lâchers d’auxiliaires. Mais l’efficacité à grande échelle dépend du bon choix d’espèces, du calendrier d’intervention et de la capacité des auxiliaires à suivre le rythme des pullulations.

Collectivités et particuliers, les bons réflexes à adopter

En tant que collectivités et en qualité de citoyens, comment contribuer à cette lutte ? Il s’agit d’abord d’apprendre à reconnaître les symptômes : miellat collant, fumagine noire, rameaux couverts de « petites carapaces » brunâtres, puis jaunissement.

Il faut ensuite éviter de déplacer des branches, rameaux ou végétaux de pins depuis une zone infestée vers une zone saine, et signaler les cas aux services compétents lorsqu’un nouveau foyer est suspecté.

Enfin, dans les espaces gérés, il s’agit de prioriser les arbres les plus sensibles (pins parasols, sujets en bord de route ou en ville) et intervenir le plus tôt possible : une fois l’arbre très affaibli, les chances d’inverser la trajectoire sont minces.

Une autre difficulté tient au manque de connaissances scientifiques produites en France sur Toumeyella parvicornis. Les données sur sa dynamique locale (nombre de générations par an selon les microclimats et les espèces d’arbres), ses ennemis naturels réellement efficaces, ses voies de dissémination et ses interactions avec le stress hydrique et les effets post-incendies restent encore à établir. Cette lacune contraste avec la situation italienne, où plusieurs travaux récents décrivent déjà la progression, les impacts sur la croissance des pins et des outils de suivi (dont la télédétection) qui peuvent aider les gestionnaires.

L’urgence en France, pour la recherche, est donc de cartographier finement l’extension du phénomène, en utilisant la télédétection et des drones par exemple, de mesurer l’impact sur la croissance des pins et, surtout, d’identifier les régulations naturelles efficaces, qui passent par l’identification génétique des arbres.

Par exemple, quelles coccinelles et autres prédateurs ou parasitoïdes attaquent réellement la cochenille dans le Var ? À quelle période de l’année ? Avec quel niveau de contrôle ? Sans ces données, il est difficile d’évaluer ce qui marche, ce qui coûte cher pour peu d’effets, et ce qui pourrait être déployé à grande échelle sans risques écologiques secondaires.

Romain Garrouste a reçu des financements de MNHN, CNRS, Sorbonne Université, Labex BCDIV (ANR), MRAE, MTE, National Geographic,

– ref. Dans le Var, la progression de la cochenille-tortue du pin menace les paysages méditerranéens – https://theconversation.com/dans-le-var-la-progression-de-la-cochenille-tortue-du-pin-menace-les-paysages-mediterraneens-273538

March 19, 2026

Le nématode du pin, un redoutable globe-trotteur

Source: The Conversation – France (in French) – By Hervé Jactel, Directeur de recherche, Inrae

Un nématode du pin _Bursaphelenchus xylophilus_ mâle, un _Monochamus galloprovincialis_, l’insecte vecteur de la maladie du flétrissement, et un pin desséché. L. D. Dwinell, USDA Forest Service/Gilles San Martin /Mateinsixtynine, CC BY

Partout où il s’est installé, le nématode du pin Bursaphelenchus xylophilus a tué des millions d’arbres. Son arrivée dans les Landes françaises ne présage donc rien de bon. Pour lutter contre cette espèce invasive, il faut bien sûr connaître son cycle de vie et la façon dont la maladie qu’il véhicule se transmet d’arbre en arbre. C’est ce que nous explique le spécialiste d’entomologie forestière Hervé Jactel.

Le nématode du pin Bursaphelenchus xylophilus, responsable de la maladie du flétrissement, est sans conteste le pire agent pathogène pour les forêts de pin du continent eurasiatique. Il s’agit d’un ver microscopique qui, une fois dans l’arbre, se nourrit des vaisseaux du bois, et bloque la circulation de la sève. Les symptômes sont, dans un premier temps, le rougissement des aiguilles puis leur chute, ensuite la courbure des pousses (d’où le nom de flétrissement), puis enfin la mort de l’arbre en quelques semaines seulement.

*Bursaphelenchus xylophilus* (adulte mâle).
David Pires (INIAV, PT), Fourni par l’auteur

Partout où il a été introduit, il a provoqué la mort de millions d’arbres. Cette espèce exotique envahissante (classée organisme de quarantaine en Europe) est originaire d’Amérique du Nord où elle ne cause pas de dégâts, car les pins nord-américains sont résistants. En revanche, elle s’avère très agressive envers les espèces de conifères avec lesquelles elle n’a pas longtemps cohabité.

Une série d’invasions en Asie

Comme pour toutes les espèces invasives, le nématode du pin se joue des frontières terrestres ou maritimes. Il est arrivé en 1905 au Japon sans doute par l’intermédiaire d’une cargaison de bois venue des États-Unis. Il a, depuis, causé la perte de 95 % de la ressource en pins du pays. Il a ensuite été détecté en Chine en 1982, à Nankin (Nanjing en chinois), possiblement à cause de l’importation depuis les États-Unis de matériaux de construction d’un grand télescope. Il est désormais présent dans 18 provinces et a tué plus de 50 millions d’arbres.

Des travaux de modélisation ont montré que cette rapide expansion est surtout due à une propagation assistée par l’humain, avec des déplacements de plusieurs centaines de kilomètres par an sans doute liés au transport de matériaux en bois contaminés. Les dégâts sont tout aussi considérables en Corée (10 millions d’arbres morts en dix ans) malgré toutes les mesures d’éradication et de contrôle mises en place.

Détecté en Europe depuis 1999

Au Portugal, où il a été détecté en 1999, il occupe désormais plus de la moitié de la surface des forêts de pin maritime et a réduit de 30 % leur production. Des analyses génétiques ont montré que les populations de nématode du pin arrivées au Portugal étaient d’origine asiatique et non américaine. L’hypothèse est que du bois contaminé aurait été utilisé pour la construction de l’un des pavillons asiatiques de l’Exposition universelle de Lisbonne en 1998.

Des foyers sont également présents en Espagne depuis 2008, non loin de la frontière portugaise. Alors que certains semblent éradiqués, le foyer en Galice connu depuis une dizaine d’années est officiellement hors de contrôle et progresse de manière inquiétante.

Dans tous ces pays, le rythme de mortalité est d’environ un million d’arbres par an.

Autant dire que la menace est grave pour la forêt des Landes en France, où le pin maritime est omniprésent et où un premier foyer vient d’être découvert fin 2025 à Seignosse. Les 500 kilomètres qui séparent les foyers du nord du Portugal et de Galice du sud des Landes indiquent que, là encore, c’est le transport par l’être humain qui est à l’origine de cette invasion.

Un coléoptère qui transmet la maladie d’arbre en arbre

La maladie du flétrissement du pin est une maladie à transmission vectorielle. Le nématode du pin ne peut pas passer d’un arbre à l’autre sans l’aide de son insecte vecteur, capable de voler, qui est dans tous les pays infectés un coléoptère longicorne xylophage du genre Monochamus.

En Europe du Sud, il s’agit de l’espèce méditerranéenne Monochamus galloprovincialis. L’insecte vecteur transporte les nématodes dans ses trachées (tubes conduisant l’air aux différents organes) et les dissémine d’un arbre à l’autre à deux étapes de son cycle de développement.

Deux modes de transmission

À leur émergence de l’arbre où ils se sont développés, les jeunes adultes doivent se nourrir sur de jeunes pousses de pin en bonne santé pour acquérir l’énergie nécessaire pour faire fonctionner leurs muscles moteurs du vol et produire des ovocytes (les œufs avant leur fécondation).

C’est pendant cette phase de maturation sexuelle que l’essentiel de la charge en nématode est transmise à l’arbre. Cette transmission est passive, car les nématodes ne sont pas injectés mais sortent d’eux-mêmes des trachées, attirés par l’odeur de la résine qui s’écoule des morsures de l’insecte sur l’écorce des pousses de pin.

*Monochamus galloprovincialis* (adulte femelle), se nourrissant sur une pousse verte de pin maritime.
Inge van Halder, Fourni par l’auteur

Les nématodes gagnent alors le réseau de canaux de résine où ils peuvent se multiplier si l’arbre n’est pas résistant et si les températures sont suffisamment élevées. Le nématode du pin produit une nouvelle génération tous les quatre et cinq jours à 25 °C. En quelques semaines, la population de nématodes peut donc augmenter de façon exponentielle, conduisant à une obstruction des canaux de sève et à la mort de l’arbre par embolie.

Le deuxième mode de transmission des nématodes par les insectes vecteurs intervient, mais dans une moindre mesure, lorsque la femelle fécondée cherche un arbre hôte dépérissant pour effectuer sa ponte, car c’est l’habitat le plus favorable au développement de sa descendance.

Cet arbre peut être dépérissant parce qu’affaibli par une grave sécheresse, le passage d’un feu (les Monochamus sont attirés par l’odeur de la fumée), une attaque de scolytes (des coléoptères xylophages), une infection par un champignon ou par le nématode lui-même (si un Monochamus l’avait auparavant contaminé lors de son repas de maturation). La femelle pond ses œufs un par un dans des encoches creusées dans l’écorce des arbres. Les nématodes qui restaient dans ses trachées peuvent alors pénétrer dans l’arbre par ces blessures de l’écorce. Les jeunes larves de l’insecte creusent ensuite une galerie sous l’écorce pour se nourrir aux dépens des tissus où circule la sève de l’arbre chargée de sucres. C’est pourquoi les arbres supports de ponte ne doivent pas être morts (pas complètement secs) mais seulement moribonds.

Ensuite, les autres stades larvaires se développent lentement dans les tissus du bois alors que les nématodes survivent en se nourrissant de champignons à l’intérieur de ces mêmes tissus. Attirés par l’odeur des insectes, les nématodes présents dans le bois se regroupent dans la loge où la larve s’est transformée en nymphe et s’insèrent dans les trachées du jeune adulte avant que celui-ci n’émerge de l’arbre, emportant avec lui quelques centaines à quelques milliers de nématodes. Au total, le cycle de reproduction de l’insecte vecteur Monochamus dure un an, avec une période d’arrêt du développement pendant l’hiver.

Des coléoptères qui peuvent voler sur plusieurs dizaines de kilomètres dans leur vie

Pour boucler le cycle de la maladie, un arbre hôte doit donc être visité deux fois par des Monochamus, une fois par un Monochamus jeune adulte (mâle ou femelle) qui transmet les nématodes lors de son repas et induit donc le dépérissement de l’arbre, et une deuxième fois par un Monochamus femelle fécondée, attirée par l’arbre dépérissant, et dont les insectes de la génération fille assurent la récupération puis le transport des nématodes hors de l’arbre infecté.

Les insectes vecteurs de l’espèce M. galloprovincialis sont doués d’une grande capacité de vol, capables de se déplacer sur plusieurs dizaines de kilomètres durant toute leur vie d’adulte.

Monochamus galloprovincialis (adulte mâle) prêt à s’envoler — *Monochamus galloprovincialis* (adulte mâle), prêt à s’envoler.
Gilles San Martin, Fourni par l’auteur

Contrairement aux incendies de forêt qui ravagent en quelques jours des grandes surfaces de plantations de pin, si elle n’est pas éradiquée, la maladie du flétrissement provoquée par le nématode progresse inéluctablement mais lentement, de quelques kilomètres par an, avec une petite proportion d’arbres morts par parcelle chaque année (5 à 10 %). Il conviendrait donc d’envisager d’ores et déjà des mesures pour ralentir le front de progression de la maladie, en cas d’échec de l’éradication, et pour reconstituer les forêts impactées.

Le temps long du dépérissement des forêts infectées par le nématode du pin devrait donc permettre d’évaluer différentes options de renouvellement forestier.

Hervé Jactel ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d’une organisation qui pourrait tirer profit de cet article, et n’a déclaré aucune autre affiliation que son organisme de recherche.

– ref. Le nématode du pin, un redoutable globe-trotteur – https://theconversation.com/le-nematode-du-pin-un-redoutable-globe-trotteur-277438

March 19, 2026

Where did the ancient Greeks and Romans think lightning came from? Hint: not just the gods

Source: The Conversation – Global Perspectives – By Peter Edwell, Associate Professor in Ancient History, Macquarie University

Is it any wonder ancient people thought lightning came from the gods? Even today a close lightning strike feels like a terrifying brush with the supernatural.

Some ancient thinkers, however, suspected the gods had nothing to do with it.

They wondered, centuries ahead of their time, if lightning was related somehow to the movement of air and clouds.

A reminder of power and wrath

In the mythology of ancient Greece and Rome, thunder and lightning strikes were the prime weapon of Zeus (the king of the gods, known to the Romans as Jupiter). Reminders of his power and wrath via lightning strikes were everywhere.

The ancient Greek poet Hesiod (who was writing around 700 BCE, about the same time as Homer) described Zeus hurling bolts of lightning and thunder at his divine enemies. Zeus also struck humans such as the mythical King Salmoneus as punishment for demanding his subjects worship him as a god.

Surviving Greek and Roman statues depict Zeus hurling lightning bolts as his chief weapon of power.

For the Romans, Jupiter and the gods more generally intervened dramatically in human affairs via lightning strikes. They were often a clear indication of divine displeasure.

The father of Pompey, one of Rome’s most powerful Republican generals, was killed in 87 BCE by lightning (according to one version of the story). He was conducting a military campaign in the middle of a civil war. According to the Roman writer Plutarch, Pompey’s father was one of Rome’s most hated generals. For many at the time, the gods had dispensed justice.

In about 125 CE, the well-travelled emperor Hadrian climbed Mount Casius in Syria to view the sunrise. When he offered a sacrifice to Zeus/Jupiter, to whom the mountain was sacred, a lightning bolt killed both the attendant and sacrificial victim. Hadrian himself was spared.

In 283 CE, the Roman emperor Carus wasn’t so lucky. He was struck and killed by lightning while on campaign against the Persians. One ancient account claimed Carus was killed because he campaigned further than the gods allowed.

In the fourth century CE, the Greek writer Libanius was struck by lightning while reading a play of Aristophanes. He would suffer from debilitating headaches and other afflictions for the rest of his life.

Complex rituals and a gift from the gods

Occasionally, lightning was sent by the gods to aid an emperor in battle. When Marcus Aurelius campaigned against a tribal group in the 160s CE, lightning bolts scattered the enemy.

According to the church historian, Eusebius, the legion accompanying him was, from then on, known as the thundering legion (Fulminata).

Roman religious practice ordered complex rituals surrounding the ground struck by lightning. In what was known as the Bidental Ritual, priests purified the affected spot. It was then sealed off and forbidden to be walked on or even looked at.

Even the emperor Constantine, a supporter of Christianity from early in his reign, ordered the performance of traditional pagan rites when public buildings were struck by lightning in 320 CE.

‘That’s not Zeus up there’

While many believed fervently that lightning was an instrument of angry gods, not all were convinced.

In The Clouds, an ancient Greek play by Aristophanes (who lived around 448 to 380 BCE), the philosopher Socrates exclaimed in the middle of a thunderstorm

That’s not Zeus up there – it’s a vortex of air.

The first century CE Roman philosopher Seneca believed

clouds that encounter each other with little force cause flashes of lightning; if impelled by greater violence, thunderbolts.

He didn’t see a role for the gods in producing either phenomenon.

One in a million

Of course, many other ancient cultures believed lightning (and thunder) had religious significance.

In Zoroastrianism, a key religion of ancient Persia, lightning produced the fastest fire of 16 different types of fire.

Fire was central to the worship of Ahura Mazda, the supreme god of Zoroastrianism.

For the Kunwinjku people of Arnhem Land in northern Australia, the ancestral being Namarrkon embodied lightning and thunder. He used stone axes to split the clouds and bolts of lightning as weapons.

The United States Centre for Disease Control estimates that around 40 million lightning strikes hit the ground in the US each year. But the chances of being struck in any one year are incredibly rare at less than one in a million.

Very few of us would still see lightning as a weapon of the gods. But when lightning strikes today, it might still evoke a sense of supernatural power and foreboding.

Peter Edwell receives funding from the Australian Research Council.

– ref. Where did the ancient Greeks and Romans think lightning came from? Hint: not just the gods – https://theconversation.com/where-did-the-ancient-greeks-and-romans-think-lightning-came-from-hint-not-just-the-gods-270797

March 19, 2026

How the law of naval warfare applies to the Strait of Hormuz

Source: The Conversation – Global Perspectives – By Natalie Klein, Professor, Faculty of Law, UNSW Sydney

The Strait of Hormuz is a narrow body of water adjacent to Iran and Oman, which connects the Persian Gulf to the Gulf of Oman.

While it is a shared body of water between Iran and Oman, Iran functionally exercises a greater amount of control over it.

The strait is a vital conduit for the shipment of oil, gas and other exports (notably fertiliser) from the Persian Gulf to the rest of the world. At its narrowest point, it is just 21 nautical miles (24 miles or 39 kilometres) wide.

With the ongoing conflict between Iran, Israel and the United States, Iran has restricted the movement of ships through this waterway, causing global repercussions for oil supply and trade in other important commodities.

Can Iran do this under international law? And can the US lawfully send military convoys through the strait to protect international shipping?

What is its legal status during times of peace?

The Strait of Hormuz is used for international navigation between two high seas areas. As such, it is defined as an international strait under international law.

Even though these waters are subject to the sovereignty of the adjacent states, all other states’ ships have navigational rights through the strait.

So as long as those ships pass through the strait continuously and expeditiously, the coastal states should not take any steps to prevent their passage.

What about during war?

Once there are armed hostilities between two (or more) states, the law of armed conflict – or international humanitarian law – applies.

The law of naval warfare is part of the law of armed conflict.

Some laws of naval warfare can be traced back to the Hague Conventions adopted at the start of the 20th century.

Most commonly, states will rely on the 1994 San Remo Manual on International Law Applicable to Armed Conflicts at Sea.

Under the law of naval warfare, states are generally divided between belligerents (those engaged in armed hostilities) and neutrals (those not involved in the war).

The line between belligerents and neutrals is not always an easy one to draw. In the Middle East, at a minimum, Iran, Israel and the US could be classified as belligerents.

According to the San Remo Manual, ships flagged to neutral states, including their warships, may exercise their navigational rights under general international law through a belligerent’s strait.

It is recommended that neutral warships give notice of their passage as a precautionary measure. A belligerent must not target neutral ships – they are not considered military objectives and must not be fired upon.

During this conflict, Iran’s territorial sea (which includes the waters within the Strait of Hormuz) counts as an area of naval warfare. The belligerent states are legally required to have due regard for the legitimate rights and duties of neutral states in an international strait.

But legal protection for neutral commerce is weak. Many ships have avoided the strait – and will continue to do so – during this conflict.

Can Iran close the strait during times of war?

In line with the San Remo Manual, straits under the sovereignty of neutral states must remain open for transit passage for both neutral and belligerent shipping.

However, belligerent states are not similarly required to keep their straits open.

Can convoys lawfully be used to protect commercial shipping?

Convoys typically involve warships travelling with a fleet of merchant ships to deter and protect against attacks from belligerents during passage.

They have been used previously in the Strait of Hormuz and in the Persian Gulf.

But merchant vessels may become military objectives and subject to attack by belligerents if they travel in a convoy with belligerent warships. So any cargo vessel being escorted by a US warship places itself in danger, as it may be lawfully attacked by Iran.

If warships belonging to neutral states escort cargo ships that are also flagged to neutral countries, these merchant vessels are not military objectives, in accordance with the San Remo Manual.

A belligerent warship would, however, have a right to visit and search these ships to ensure they are not carrying contraband to the enemy.

To minimise this risk, neutral states would need to provide Iran with information as to what each ship is carrying.

What about Australian ships?

Iran may question Australia’s status as a neutral state in light of its offer to assist the United Arab Emirates as a measure of collective self-defence against Iranian attacks.

If Australia’s actions render it a “party to the conflict” under the law of armed conflict, it is no longer a neutral state – it is now a belligerent.

Its warships, along with any private vessels escorted in the strait, could then potentially be subject to lawful attack by Iran.

Natalie Klein has previously received funding from the Australian Research Council for research on maritime security and international law.

– ref. How the law of naval warfare applies to the Strait of Hormuz – https://theconversation.com/how-the-law-of-naval-warfare-applies-to-the-strait-of-hormuz-278653

March 19, 2026

Soaring gas prices prompt Trump to ease oil tanker rules – how waiving the Jones Act affects what you pay at the pump

Source: The Conversation – USA (2) – By Christopher Niezrecki, Director of the Center for Energy Innovation, UMass Lowell

Suspending the Jones Act allows foreign-based oil tankers to sail between U.S. ports. AP Photo/Eric Gay

The Trump administration temporarily suspended the Jones Act on March 18, 2026, as part of its efforts to bring down soaring U.S. gasoline prices.

But what does this more-than-century-old law, which originally was designed to support the shipping industry, have to do with the price of gas?

As the director of the Center for Energy Innovation at UMass Lowell, I’ve learned that the impact of the Jones Act ripples beyond shipping and can have a profound effect on the price of many things, including consumer goods, electricity and what you pay at the pump.

What is the Jones Act?

The Jones Act is more formally known as Section 27 of the Merchant Marine Act of 1920.

One of the act’s most impactful features is its ability to limit domestic maritime shipping and coastal trade. Under the act, a foreign-designated ship is not allowed to transport goods between two U.S. ports or territories without either leaving U.S. waters first or transporting those goods to a U.S.-flagged vessel – which must be staffed primarily by U.S. sailors.

The federal law was originally intended to bolster and protect the American maritime industry by ensuring that the U.S. has the infrastructure and personnel to support shipping, commerce, defense and naval operations needed during war or national emergencies. Since then, the act has been revised and updated numerous times.

This rule helps to protect the U.S. shipbuilding industry from foreign competition and the jobs of American sailors; however, it also limits free trade.

a sign listing high gas prices can be seen as a car drives away in the snow — Gas prices in some states have climbed higher than $5 per gallon, such as in Bellevue, Wash.
AP Photo/Lindsey Wasson

Benefits and costs

Proponents of the Jones Act claim that it supports the transport of goods between states and territories, enhances national security and helps to sustain hundreds of thousands of American jobs as well as the shipbuilding industry, while contributing billions of dollars to the U.S. economy.

However, critics of the Jones Act claim that it increases the cost of goods between U.S. ports and especially in regions that rely heavily on marine transport, such as Alaska, Hawaii and Puerto Rico.

And despite the ostensible intent to protect the shipbuilding industry, the act has also hurt it because it has made U.S. ships up to five times more expensive to build than those manufactured abroad.

These factors have resulted in a smaller supply of American ships that are available to transport goods. And when there is limited competition, costs of ship construction and transportation increase.

Impact on gas prices

The average price of a gallon of gas has soared nearly a third since the U.S. and Israel attacked Iran on Feb. 28, 2026 – from $2.98 to $3.84 as of March 18, according to data compiled by AAA.

Suspending the Jones Act allows foreign ships to transport oil and gas between ports within the U.S., which should lead to lower transportation costs and increased supply. This should ease gas costs over time – but we’re talking months, not days or weeks.

In 2022, analysts at JPMorgan estimated that a temporary suspension of the Jones Act could save East Coast motorists about 10 cents a gallon.

However, if the duration of the suspension is short – the government said it would waive the act for only 60 days – the impact on gas prices will be minimal because of the time required for the marine industry to respond and the fact that domestic shipping costs are not the primary factor that influences fuel cost.

Should the Jones Act be permanently repealed, fuel prices would fall more steeply.

The Jones Act has been temporarily suspended in the past, primarily for urgent economic or supply chain issues, such as to aid Puerto Rico after it was hit by a hurricane in 2022 and following a cyberattack on a fuel pipeline in 2021.

cars can be seen driving forward in several lanes on a major highway — Americans’ daily commutes have become more expensive since the war in Iran began on Feb. 28.
AP Photo/Paul Sancya

Other impacts of the Jones Act

Another important cost impact of the Jones Act involves offshore wind energy.

It has been shown that the energy generated by offshore wind farms provides additional energy close to load centers – cities or industrial sites that consume significant power – helping to reduce costs by providing additional supply. This is especially important now and will become more important over the next few years, as electricity demands are expected to increase due to rapid growth in artificial intelligence data centers.

The numerous approved wind farms currently being constructed off the U.S. coast are constrained by the Jones Act because there aren’t enough U.S.-flagged ships available to install and service all the offshore wind turbines that are needed. Many wind farm developers are skirting the issue by leveraging U.S. barges to transport equipment prior to installation by foreign vessels. But even so, the Jones Act raises the cost of offshore wind farm installations, making energy less affordable for Americans.

Suspending the Jones Act for a couple of months, however, will have minimal impact on the U.S. offshore wind and other energy industries.

Christopher Niezrecki receives funding from the National Science Foundation, Office of Naval Research, Massachusetts Clean Energy Center, ARROW Center, and several companies that support the WindSTAR Industry-University Cooperative Research Center.

– ref. Soaring gas prices prompt Trump to ease oil tanker rules – how waiving the Jones Act affects what you pay at the pump – https://theconversation.com/soaring-gas-prices-prompt-trump-to-ease-oil-tanker-rules-how-waiving-the-jones-act-affects-what-you-pay-at-the-pump-278387

March 18, 2026

The case for combined events: How decathlon and heptathlon training could solve a crisis in youth sport

Source: The Conversation – Canada – By Kurt Michael Downes, PhD Candidate, Kinesiology, University of Windsor

When the World Athletics Indoor Championships get underway in Kujawy Pomorze, Poland, on March 20, be sure to tune in to the men’s seven-event heptathlon and the women’s five-event pentathlon.

The move indoors means there are fewer events compared to the men’s decathlon (10 events) and women’s heptathlon held at outdoor events like the World Athletics Championships in Tokyo last fall and the Olympics, but these events deserve the spotlight — and not just for the incredible athleticism.

The real lessons these events offer have less to do with medals and extend far beyond winning and losing. Instead, this sport setting provides an opportunity to reimagine how we develop athletes. What if the blueprint for building better athletes isn’t about doing multiple sports, but instead about doing multiple events?

Each year, North American sport is confronted with the same problem: Growing numbers of children are pressured by parents, coaches and leagues to commit to a single sport. Before they even reach their teens, kids are “encouraged” (and by encouraged we mean pressured) to spend more time specializing in their sport to gain a competitive edge. Yet, research suggests the opposite is true: Studies consistently link early specializaton to burnout, higher rates of overuse injuries and sport dropout.

Interestingly, this paradox suggests the very pathway thought to build champions often pushes promising athletes out of sport. An alternative may be found in track and field’s combined events. The decathlon and heptathlon require athletes to run, jump and throw across a slate of events, unlike single-sport specialists.

The advantage is that the combined events allow athletes to develop every major athletic quality: speed, power, endurance, agility and strength. When you add both linear and rotational movements, you get one of the most complete athlete-development systems in sport.

In essence, the combined events represent a more updated and advanced version of the Long-Term Athlete Development Plan, a program designed to outline appropriate stages of athletic growth, build on fundamental movement skills and develop sport-specific competency while reducing injury and burnout.

As such, we ask whether a run-jump-throw system based on the combined events model could be the answer to early specialization in youth sport.

The problem of early specialization

Early sport specialization often refers to year-round participation in a single sport, a trend now common across youth athletics. Examples include young hockey, basketball and soccer players who are pushed toward club or academy teams with daily programs to stay competitive and ensure the “right” people can see them play.

These clubs and academies come with hefty tuition, major travel expenses and logistics, and they may even require kids to leave home and find room and board.

But even outside these commitments, young athletes and their families often feel the need to hire extra personal skills trainers, find additional practice time, compete on multiple teams and more throughout the year in order to keep up with their peers and squeeze every ounce of performance out of their young bodies in and out of season. Once involved in a youth sport at a competitive level, there is no time (or money) for other sports.

At first glance, practice and competition in a single sport seems like a surefire plan for success; with a “more hours equals better” mindset, how could it not? Unfortunately, research tells a different story. Studies consistently show that early specialization is not the most effective pathway to high performance, and a singular focus on one sport instead becomes a risky gamble in long-term athlete development.

Kids who focus on one sport routinely face repetitive overuse injuries, ranging from stress fractures to tendinitis and the loss of motivation to participate in sport.

What’s most concerning is that youth sport dropout rates average roughly 35 per cent per year, and early specialization is consistently linked with even higher dropout risk driven by less play, more pressure and an unbalanced developmental path.

Enter the combined events

Since reports suggest early specialization limits an athlete’s growth, we suggest looking to one of sport’s most multifaceted disciplines as the remedy. In track and field, the decathlon and heptathlon demand a broad skill set that spans the full range of athletic abilities.

Over the course of two demanding days, combined-event athletes sprint, hurdle, jump, throw and run. Scaled-down developmental versions also exist, offering age- and skill-appropriate movements instead of early mastery of a single sport.

This diversity can also align with what sport scientists describe as windows of trainability: periods when young athletes are especially primed to develop speed, agility, co-ordination and endurance. Training across multiple disciplines ensures these important windows of development are not missed.

The difference with early specialization is undeniable. While a young soccer player may log thousands of contacts with the ball by age 12, an athlete in youth combined events is learning to hurdle, jump, throw and pace distance runs. This variety builds broad physical literacy, spreads stress across the body and reduces the overuse injuries common in single-sport pathways. It provides the range, balance and adaptability youth athletes need in order to avoid the pitfalls of early specialization.

An outdoor sports events with a young woman landing a long jump in the foreground — Scaled-down developmental versions of combined events exist, offering age and skill-appropriate movements instead of early mastery of a single sport.
(Pexels/Chris I)

Why it matters for kids in sport

Ultimately, the combined events are the antidote for early specialization. Training across the sprints, jumps, throws and distance events keeps kids moving in different ways and across different planes. It avoids the monotony and repetitive stress that pushes so many away from sport.

Long-term athlete development models, which are the gold standard of athlete development across sports, promote broad skill development. Here’s why there’s such a strong case for the combined events:

Fewer injuries: Combined-event training spreads physical stress, lowering the risk of overuse injuries. Research shows that early specialization increases injury risk, while variety builds resistance..
Stronger foundations: A mix of running, jumping and throwing helps develop comprehensive physical literacy through a wide mixture of skills, which in turn allows athletes to grow healthier and reach higher levels in sport.
More fun, less burnout: Keeping practices fresh with new challenges increases motivation. It reduces burnout and keeps kids engaged in sport..

For parents, coaches, schools, clubs and policymakers, the combined events have a format that can be easily delivered and easily integrated into youth sport. As an example, a youth athlete playing soccer (the most highly participated sport in Canada for ages five to 17), can become more athletically proficient during the off-season.

The goal is not to replace soccer. Instead, introducing the principles of combined events can enhance performance and enjoyment. First-step acceleration helps with breakaway speed, jumping develops power for change of direction and throwing builds muscular co-ordination and trunk strength. The combined events’ weekly rotation through sprints, jumps, throws and endurance work is supported by science.

Burnout to balance

Early specialization can look like a shortcut, but it often leads to injuries, burnout and kids leaving sport. The path meant to create champions can end careers before they start.

Combined events offer a better way, blending power, endurance, technical skill and adaptability.

The science is clear: broad experiences in childhood lay the best foundation for long-term success. Most kids won’t become decathletes or heptathletes, but the message is simple: variety matters, but only when it’s balanced, intentional and developmentally appropriate. The right mix of skills develops better young athletes and keeps them engaged.

Kurt Michael Downes receives funding from the Coaching Association of Ontario (CAO). He is the President and Head Coach of the Border City Athletics Club (a not-for-profit organization) and serves on the boards of Family Fuse and Resilient Kids Canada (both not-for-profit organizations).

Kevin Milne does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. The case for combined events: How decathlon and heptathlon training could solve a crisis in youth sport – https://theconversation.com/the-case-for-combined-events-how-decathlon-and-heptathlon-training-could-solve-a-crisis-in-youth-sport-270263

March 18, 2026

OpenAI’s safety pledges in the wake of Tumbler Ridge aren’t AI regulation — they’re surveillance

Source: The Conversation – Canada – By Jean-Christophe Bélisle-Pipon, Assistant Professor in Health Ethics, Simon Fraser University

In a span of two days following news that the Tumbler Ridge perpetrator’s ChatGPT account had been flagged prior to the shooting, OpenAI CEO Sam Altman met with Federal AI Minister Evan Solomon and British Colombia Premier David Eby.

He secured commitments on both sides: reporting threats directly to the RCMP, retroactive review of previously flagged accounts, distress-redirect protocols, access to the company’s safety office for Canadian experts and an agreement to work with B.C. on regulatory recommendations to Ottawa.

He also agreed to apologize to the community of Tumbler Ridge, where 18-year-old Jesse Van Rootselaar killed eight people and wounded many others before dying of a self-inflicted wound. Months prior to the shooting, Van Rootselaar’s ChatGPT account had been flagged for scenarios involving gun violence. The account was banned, but not reported to law enforcement.

OpenAI’s new commitments are significant gestures. But they resolve a narrower question than the one Tumbler Ridge actually raised. As I argued earlier, the core problem was not a reporting failure. It was a governance vacuum.

What’s changed since? OpenAI has agreed to make the same type of unilateral determination it made before, but to act on it more aggressively, routing the result directly to the RCMP. That is not a fix. It is the same unaccountable architecture with a faster trigger.

The human-in-the-loop fallacy

Consider what we now know about the internal process. The shooter’s account was flagged. Human moderators reviewed the interactions. Some advocated escalating to law enforcement. Other humans, guided by the company’s own opaque thresholds, decided against it. The breakdown was not mechanical. It was institutional.

“Human in the loop” is one of the most repeated reassurances in AI safety discourse. The Tumbler Ridge case exposes its limits. Humans in the loop are only as accountable as the institutional structure around them. When that structure is a private corporation with no legally binding reporting obligations, no transparency requirements and no external oversight, the human in the loop is simply a more sympathetic face on an unaccountable system.

OpenAI has since announced that its thresholds have been updated. But updated by whom, according to what criteria, subject to what review? These remain internal decisions, invisible to the public and unreachable by Parliament.

The surveillance substitution

There is a deeper problem that receives almost no attention. The proposed settlement does not regulate AI. It regulates users.

The entire apparatus being constructed (internal threat identification, flagging, direct RCMP referral) is oriented toward monitoring what people say to AI, not toward how AI systems are designed, trained or constrained in their responses.

True AI regulation asks whether a model might facilitate or amplify harmful ideation through its interaction patterns. It asks how the system is built, what it’s tested for and what obligations attach to its deployment.

The current arrangement asks none of these questions. Instead, it builds a pipeline from private AI interactions to law enforcement, administered by a corporation, governed by proprietary policy.

I call this the surveillance substitution: a governance vacuum gets filled not with democratic regulation, but with corporate surveillance of users. It is not regulation of AI. It is regulation of the people who use AI, conducted by the AI company itself, with the police as the endpoint.

The civil liberties implications are substantial. Research on compassion-sensitive AI, including my own work on how AI systems should respond to users in vulnerable states, consistently shows that people disclose distress to chatbots precisely because the interaction feels private and non-judgmental.

If that space becomes a monitored channel where concerning disclosures trigger law enforcement referrals based on opaque corporate criteria, the most vulnerable users may stop disclosing. The chilling effect on help-seeking behaviour has not been studied, and it has not been discussed in any of the public negotiations following Tumbler Ridge.

Rational strategy, absent framework

It’s important to be precise about what OpenAI is doing. The company is not acting in bad faith. It is behaving as a rational private entity in the absence of a regulatory framework, offering the minimum viable response to political pressure while preserving as much operational autonomy as possible.

Look south and the logic becomes clearer. In the United States, the relationship between AI companies and government power is being forcibly renegotiated. The Pentagon has sought AI models with safety guardrails removed for military applications. When Anthropic resisted, OpenAI moved to fill the gap. In that context, the U.S. government commands and AI companies comply.

In Canada, the dynamic is inverted: OpenAI is not being commanded. It is volunteering concessions designed to pre-empt the kind of binding legislation that would actually constrain its operations. Support broad norms with no immediate legal force; resist specific domestic obligations that carry real consequences. This is how regulatory capture begins: not with corruption, but with convenience.

Canada has genuine leverage here: an unusual cross-party consensus that something must change, public attention that has given AI governance a human face, and a provincial government that understands the stakes.

But leverage evaporates. If the federal government accepts OpenAI’s pledges as a sufficient response, it normalizes corporate self-regulation as the baseline. Future companies will cite this arrangement as precedent. The window for legislation narrows.

What durable governance requires

The response that Tumbler Ridge demands is not more efficient surveillance of users. It is a regulatory architecture that addresses the systems themselves.

That means binding legislation with legally defined thresholds for when AI companies must refer flagged interactions to authorities: thresholds defined by Parliament, developed with mental health professionals, privacy experts and law enforcement, not inherited from a company’s terms of service.

It means an independent triage body so that flagged interactions are assessed by professionals equipped to distinguish ideation from intent, accountable to public law rather than corporate liability. And it means model-level accountability: regulatory attention that moves upstream from users to systems. How are these models designed to respond to escalating disclosures of violent ideation? What testing obligations apply? What auditing requirements exist?

These questions are absent from the current political negotiations, and their absence defines the limits of what the current pledges can achieve.

OpenAI’s commitments following Tumbler Ridge are the beginning of a conversation, not the end of one. Canada holds good cards. The question is whether it plays them, or lets the other side set the rules while the table is still being built.

Jean-Christophe Bélisle-Pipon does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. OpenAI’s safety pledges in the wake of Tumbler Ridge aren’t AI regulation — they’re surveillance – https://theconversation.com/openais-safety-pledges-in-the-wake-of-tumbler-ridge-arent-ai-regulation-theyre-surveillance-278364

March 18, 2026

Lorsque la guerre prend des allures de prophétie : comment les récits apocalyptiques américains façonnent la guerre contre l’Iran

Source: The Conversation – in French – By André Gagné, Full Professor, Department of Theological Studies, Concordia University

Après que les États-Unis et Israël ont commencé à bombarder l’Iran, tuant certains des plus hauts dirigeants du gouvernement, dont le Guide suprême Ali Khamenei, ainsi que plus de 1 000 civils, certains des partisans évangéliques les plus fidèles de Trump ont rapidement présenté le conflit en termes de guerre religieuse.

Le matin des attaques, le prédicateur américain Franklin Graham, président de la Billy Graham Evangelistic Association et fondateur de Samaritan’s Purse, a publié sur X : « Priez pour nos militaires engagés dans l’opération contre l’Iran, pour le président @realDonaldTrump, et pour que le peuple iranien soit libéré de l’asservissement de l’islam. »

Dans mon livre, Ces évangéliques derrière Trump : hégémonie, démonologie et fin du monde, j’explique comment le dispensationalisme prémillénariste, une des grilles d’interprétation contemporaines de la fin des temps, demeure largement influente parmi les évangéliques américains. Le dispensationalisme fonctionne pour certains évangéliques à la fois comme une méthode d’interprétation biblique et comme un cadre pour en comprendre l’histoire. Les « dispensations » désignent des périodes distinctes de l’histoire, chacune instituée par Dieu pour régir et structurer l’ordre du monde.

Le dispensationalisme enseigne que le Christ reviendra avant la fin des temps afin d’établir sur Terre un règne de paix et de justice d’une durée de mille ans, communément appelé le Millénium.

Une feuille de route méthodique

Depuis l’attaque américaine contre l’Iran, Greg Laurie, fondateur et pasteur de la Harvest Christian Fellowship en Californie, a réalisé une série de vidéos promouvant sa lecture dispensationaliste de l’actualité. Pour Laurie, le prochain événement sur « le calendrier de Dieu » est l’enlèvement de l’Église (Rapture), moment où les croyants « nés de nouveau » sont ravis au ciel. Dans certaines interprétations des prophéties bibliques, l’enlèvement est suivi de la Grande Tribulation, une période de tourmente de sept ans. Certains croient que durant cette période, le peuple juif reconstruira son temple à Jérusalem, que des jugements divins frapperont la Terre et qu’une figure politique connue sous le nom d’Antéchrist accédera au pouvoir.

Cette période culmine dans une confrontation finale entre Jésus et les nations rassemblées par l’Antéchrist contre Israël appelée Armageddon. Après ce conflit, le Christ doit établir son règne millénaire depuis Jérusalem, où les nations du monde seront placées sous son autorité.

Certains évangéliques interprètent la lutte entre l’Iran et Israël à travers ce même prisme eschatologique.

Selon leur lecture, l’Iran, connu dans l’Antiquité sous le nom de Perse, serait identifié dans certains textes prophétiques comme l’une des nations destinées à jouer un rôle dans un conflit décrit dans Ézéchiel 38–39, souvent appelé la bataille de Gog et Magog.

L’influenceuse évangélique Traci Coston a également utilisé un argument numérologique pour renforcer la caractérisation de Trump comme un nouveau roi Cyrus, une idée popularisée par Lance Wallnau, un entrepreneur pentecôtiste influent. Coston écrit que l’Iran « vit sous un régime islamique oppressif depuis 47 ans » et souligne que Donald Trump est le 47^e président des États-Unis. Elle le compare à « un dirigeant politique païen » que Dieu aurait oint « pour briser des verrous et infléchir le cours de l’histoire au profit de Son peuple ».

Trump a tiré parti de telles caractérisations à son égard et a repartagé sur son compte Truth Social, le 9 mars, une prophétie de 2007 faite par Kim Clement, un musicien, pasteur et figure prophétique populaire décédé en 2016.

Combat spirituel et réveil de la fin des temps

Parmi certains dirigeants pro-Trump des milieux néo-pentecôtistes et néo-charismatiques, le conflit avec l’Iran est interprété comme un combat spirituel. Ils lisent les événements mondiaux comme les manifestations d’un affrontement continu entre forces divines et démoniaques, et estiment que la prière des chrétiens contribue à contenir, voire à repousser, ce qu’ils perçoivent comme des puissances maléfiques.

La veille de l’attaque, Lou Engle, prophète néo-charismatique américain, rappelle qu’en 2006, un groupe de soixante-dix croyants s’était rassemblé à Boston pour une période de prière continue de quarante jours et quarante nuits. Il cite la prophétie de Jérémie 49,34-38, qui annonce le jugement contre Élam – une région antique correspondant au sud de l’Iran actuel. S’appuyant sur ce passage, il affirme que les fidèles avaient prié pour que « Dieu brise l’arc de l’islam et établisse Son trône en Iran ».

Déjà des milliers d’abonnés à l’infolettre de La Conversation. Et vous ? Abonnez-vous gratuitement à notre infolettre pour mieux comprendre les grands enjeux contemporains.

La fête juive de Pourim, célébrée les 2 et 3 mars, a aussi été instrumentalisée pour présenter le conflit actuel comme un combat spirituel.

Ce paradigme du combat spirituel puise ses racines dans la lecture que font certains dirigeants pentecôtistes pro-Trump des textes bibliques, où ils voient des affrontements cosmiques. C’est notamment le cas de Daniel 10,12-21, où des forces surnaturelles interviennent et influencent les conflits entre nations. En s’appuyant sur ces passages bibliques, des partisans influents de ce paradigme, comme Wallnau, affirment que c’est un « esprit territorial » qui alimente les conflits. Selon eux, seul le combat spirituel peut déloger cette influence : l’objectif est de briser le pouvoir des forces démoniaques qui entravent la diffusion de l’Évangile dans les régions réfractaires au christianisme.

De nombreux dirigeants néo-pentecôtistes pro-Trump adhèrent à une eschatologie victorieuse, selon laquelle le Royaume de Dieu s’étendra visiblement à travers le monde et l’Église connaîtra puissance, unité, maturité et gloire avant le retour du Christ.

Ce cadre offre une autre vision de la fin des temps, dans laquelle certains anticipent un grand réveil spirituel entraînant des conversions massives au christianisme.

Une vision qui ne date pas d’hier

L’idée d’un réveil spirituel mondial à la fin des temps n’est pas nouvelle. Les premiers pentecôtistes étaient convaincus de vivre dans les derniers jours et considéraient le parler en langues comme un outil missionnaire. Grâce à cette capacité surnaturelle de parler des langues qu’ils n’avaient pas apprises, ils croyaient pouvoir parcourir le monde et proclamer l’Évangile avant le retour du Christ.

Plus tard, dans les années 1940, le mouvement connu sous le nom du Nouvel ordre de la pluie de l’arrière-saison (New Order of the Latter Rain) – qui connaît un réveil en 1948 à North Battleford, en Saskatchewan – adopte une vision similaire. Ses idées exerceront finalement une influence majeure sur le mouvement charismatique et sur les églises charismatiques indépendantes dans le monde entier. Le Nouvel ordre s’est séparé du pentecôtisme classique au Canada, dénonçant la « sécheresse spirituelle » qu’il y perçoit et cherchant à vivre une expérience spirituelle renouvelée.

Des « décisions fondées sur la théologie »

Lorsque le secrétaire d’État américain, Marco Rubio, affirme que le régime iranien prend des « décisions fondées sur la théologie, leur vision de la théologie qui est apocalyptique », et que le secrétaire à la Défense, Pete Hegseth, déclare que des « régimes fous, comme l’Iran, obsédés par des délires islamistes prophétiques, ne peuvent pas posséder d’armes nucléaires ; ce n’est que bon sens », cette rhétorique tend à présenter Téhéran comme étant uniquement mue par l’extrémisme religieux.

Pourtant, des dirigeants chrétiens alliés à Donald Trump ont été accueillis au Bureau ovale pour prier et lui imposer les mains. Trump a lui-même relayé des messages prophétiques sur son ascension politique, suggérant ainsi à ses partisans que sa présidence relevait de la volonté divine.

Le contraste est saisissant. Lorsque la croyance religieuse façonne la politique de rivaux, elle est qualifiée de théologie dangereuse, mais lorsqu’elle apparaît à Washington, elle est présentée comme une manifestation de la Providence divine.

André Gagné ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d’une organisation qui pourrait tirer profit de cet article, et n’a déclaré aucune autre affiliation que son organisme de recherche.

– ref. Lorsque la guerre prend des allures de prophétie : comment les récits apocalyptiques américains façonnent la guerre contre l’Iran – https://theconversation.com/lorsque-la-guerre-prend-des-allures-de-prophetie-comment-les-recits-apocalyptiques-americains-faconnent-la-guerre-contre-liran-278747

March 18, 2026

Hundreds of hungry mosquitoes, a student volunteer and a mesh suit helped us figure out how these deadly insects reach their targets

Source: The Conversation – USA – By David Hu, Professor of Mechanical Engineering and Biology, Adjunct Professor of Physics, Georgia Institute of Technology

Trajectories of mosquitoes flying around a human target. David L. Hu, Georgia Tech

“Four minutes is too long.”

Man's arm with multiple pink raised welts — Some of Chris Zuo’s itchy results after his session with the mosquitoes.
David L. Hu

That’s the note undergraduate Chris Zuo sent me along with photos of countless mosquito bites on his bare skin. This full-body massacre wasn’t the result of a camping trip gone awry. He’d spent that limited amount of time in a room with 100 hungry mosquitoes while wearing nothing but a mesh suit we thought would have protected him.

Thus began our three-year journey trying to understand the behavior of a deceivingly simple insect, the mosquito. It may sound like a professor’s sadistic plan, but, really, we did everything by the book. Our university’s institutional review board approved our procedures, making sure Chris was safe and not coerced in any way. The mosquitoes were disease-free and native to our home state of Georgia. And this session resulted in the first and last bites anyone received during the study.

Besides my role as torturer of students, I am an author and professor at Georgia Tech with over 20 years of experience studying the movement of animals.

Mosquitoes are the world’s most dangerous animal. The diseases they carry, from malaria to dengue, cause over 700,000 deaths per year. More people have died from mosquitoes than wars.

The world spends US$22 billion per year on billions of liters of insecticides, millions of pounds of larvicides, and millions of insecticide-treated bed nets – all to fight a tiny insect that weighs 10 times less than a grain of rice and has only 200,000 neurons.

Yet, people are losing the war on mosquitoes. These insects are evolving to thrive in cities and spreading disease more rapidly with climate change. How can such simple animals find us so easily?

Scientists know mosquitoes have terrible eyesight and depend on chemical cues to make up for it. Knowing what attracts a mosquito, though, isn’t enough to predict its behavior. You can know a heat-seeking missile is drawn to heat, but you still won’t know how a missile works.

Enter Chris and his self-sacrifice in the mosquito room. By tracking the flight of many mosquitoes around him, we hoped to determine how they made decisions in response to his presence. Understanding how mosquitoes respond to humans is a first step to controlling them.

How mosquitoes zero in on their meal

Out of 3,500 species of mosquitoes, over 100 species are classified as anthropophilic, meaning they prefer humans for lunch. Certain species of mosquitoes will find the one person among a whole herd of cattle in order to suck human blood.

This is quite a feat considering mosquitoes are weak flyers. They stop flying in a slight 2-3 mph breeze, the same air speed generated by a horse’s swinging tail. In calmer conditions, mosquitoes use their minuscule brains to follow human heat, moisture and odors that are carried downwind.

Carbon dioxide, the byproduct of respiration of all living animals, is particularly attractive. Mosquitoes notice carbon dioxide as well as you notice the stink of a full dumpster, detecting it up to 30 feet (9 meters) away from a host, where concentrations dip to a few parts per million, like a few cups of dye in an Olympic-size pool.

Black outline of a G and T in left panel, in right panel black squiggles showing flight paths of mosquitoes around the letters — Like superfans, mosquitoes are drawn to the dark outline of the Georgia Tech logo.
David L. Hu, Georgia Tech

Mosquitoes’ vision isn’t much help as they hunt for their next blood meal. Their two compound eyes have several hundred individual lenses called ommatidia, each about the width of a human hair. They produce a somewhat blurry mosaic or pixelated image. Due to the laws of optics, mosquitoes can discern an adult-size human only at a few meters away. With their vision alone, they cannot distinguish a human from a small tree. They inspect every dark object.

Gathering the flight-path data

The challenge with studying mosquito flight is that, like trash-talking teenagers, most of what they do is meaningless noise. Mosquitoes flying in an empty room are largely making random changes in flight speed and direction. We needed many flight trajectories to cut through the noise.

A man lying on the ground, and shown in two images on a laptop screen in the foreground — In a mesh suit, Chris Zuo awaits the mosquitoes while questioning his life choices.
David L. Hu, Georgia Tech

One of our collaborators, University of California, Riverside, biologist Ring Cardé, told us that back in the 1980s, scientists conducted “bite studies” by stripping down to their underwear and slapping the mosquitoes that landed on their naked bodies. He said nudity prevented confounding variables, such as the color of a shirt’s fabric.

Chris and I looked at each other. Sit naked and wait to become mosquito prey? Instead, we designed the mesh suit that Chris originally wore into the mosquito room. But after seeing Chris’ bites, we needed a better way.

Instead, Chris washed long-sleeved clothes in unscented detergent and wore gloves and a face mask. Fully protected, Chris only had to stand and wait, while a cloud of mosquitoes swarmed him.

The U.S. Centers for Disease Control and Prevention introduced us to the Photonic Sentry, a camera that simultaneously tracks hundreds of flying insects in a room. It records 100 frames per second at 5 mm resolution for a space like a large studio apartment. In just a few hours, Chris and another graduate student, Soohwan Kim, generated more mosquito flight data than had previously been measured in human history.

100 mosquitoes flying around Chris Zuo for 10 minutes. Only a fraction of tracks are shown.

Jörn Dunkel, Chenyi Fei and Alex Cohen, our mathematician collaborators at MIT, told us that the geometry of Chris’ body was still too complicated to study the mosquitoes’ reactions. Mathematicians excel at simplifying complex problems to their essence. Chenyi suggested we go easy on Chris – why not replace him with a simple dummy: a black Styrofoam ball on a stick combined with a canister of carbon dioxide.

Over the next two years, Chris filmed the mosquitoes circling the Styrofoam dummies mercilessly. Then he vacuumed up the mosquitoes, trying not to get bitten.

Deciphering the trajectories

A mosquito flies like you would an airplane: it turns left or right, accelerates or hits the brakes. We determined a mosquito’s flight behavior as a function of its speed, location and direction with respect to the target as the first step in creating our model of their behavior.

Our confidence in our behavioral rules increased as we read more trajectories, ultimately using 20 million mosquito positions and speeds. This idea of incorporating observations to support a mathematical hypothesis is a 200-year-old idea called Bayesian inference. We illustrated the mosquito behavior we’d observed in a web application.

4 panels showing trajectory of a mosquito in the presence of no target, visual target, CO2 target or both. — A mosquito’s flight changes with the kind of target presented.
David L. Hu

Using our model, we showed how different targets cause mosquitoes to fly differently. Visual targets cause fly-bys, where mosquitoes fly past the target. Carbon dioxide causes double takes, where mosquitoes slow down near the target. The combination of a visual cue and carbon dioxide creates high-speed orbiting patterns.

Up until now, we had used only experiments with Styrofoam spheres to train our model. The true test was whether it could predict mosquito flights around a human. Chris returned to the chamber, this time wearing all white clothes and a black hat, turning himself into a bull’s-eye. Our model successfully predicted the distribution of mosquitoes around him. We identified zones of danger, where there was a high chance of a mosquito circling around him.

Predicting mosquito behavior is a first step toward outsmarting them. In mosquito-prone areas, people design houses with features to prevent mosquitoes from following human cues and entering. Similarly, mosquito traps suck in mosquitoes when they get too close but still allow between 50% and 90% of mosquitoes to escape. Many of these designs are based on trial and error. We hope that our study provides a more precise tool for designing methods for mosquito capture or deterrence.

When Chris’ mother attended his master’s degree defense, I asked her how she felt about her son using himself as bait for mosquitoes. She said she was very proud. So am I – and not just because I’m relieved Chris didn’t ask me to take his place in the mosquito chamber.

David Hu does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Hundreds of hungry mosquitoes, a student volunteer and a mesh suit helped us figure out how these deadly insects reach their targets – https://theconversation.com/hundreds-of-hungry-mosquitoes-a-student-volunteer-and-a-mesh-suit-helped-us-figure-out-how-these-deadly-insects-reach-their-targets-278486

March 18, 2026

Evangelical holy war: Why some Christians think Trump will end the world

Source: The Conversation – Canada – By Matthew Burkholder, PhD Candidate, Theological Studies, University of Toronto

Soldiers in the United States Armed Forces have lodged more than 100 complaints with the Military Religious Freedom Foundation (MRFF) stating that their commanders are using extremist religious rhetoric to describe the U.S.-Israel war against Iran.

According to some complaints, American military commanders have told their troops the attack on Iran is a holy war, and that U.S. President Donald Trump was “anointed by Jesus to light the signal fire in Iran to cause Armageddon and mark his return to Earth.”

In a recent interview with Democracy Now!, the MRFF’s president, Mikey Weinstein, said the foundation was “inundated” with calls from soldiers indicating that commanders across the armed forces “were euphoric” because the war would serve as a way to “bring their version of weaponized Jesus back.”

The comments are among other violent religious rhetoric to come from U.S. officials. The U.S. ambassador to Israel, Mike Huckabee, caused a diplomatic row when he suggested Israel had a biblical claim to take over much of the Middle East.

The language also comes as some American officials have sought to characterize the Iranian government as fanatical. Secretary of State Marco Rubio said Iran was run by “religious fanatic lunatics.” Secretary of Defense Pete Hegseth said: “Crazy regimes like Iran, hell-bent on prophetic Islamic delusions, cannot have nuclear weapons.”

Meanwhile, American televangelist John Hagee recently claimed that Russia, Turkey, “what’s left of Iran” and “groups of Islamics” would soon invade Israel and be destroyed by God.

Democracy Now video: Whistleblowers speak out about religious extremism in military amid war on Iran.

American evangelicalism

During my PhD in Christian theology, I’ve asked why some American evangelical religious movements, which have gained increasing visibility and power through President Donald Trump’s MAGA politics shaped heavily by white Christian nationalism, embrace violent interpretations of what theologians refer to as “eschatology” (a theology of end times).

While the term “evangelical Christian” is notoriously difficult to define, historian David Bebbington, who focused on these movements in the United Kingdom, delineated four broad charactersitics: a strong belief in the Bible, the death of Jesus for sins, a conversion experience and social activism.

My own research specialization is how modern Protestant Christians, including evangelical Christians, understand the significance of Jesus’s death, also referred to as the atonement, and its relationship to the end times.

Seeking Armageddon

Rhetoric about wars being religious, and Trump being divinely anointed and about to cause Armageddon, is deeply disturbing and has catalyzed condemnation from Christians in the U.S. and beyond advocating non-violent and diplomatic foreign policy.

Violent U.S. religious rhetoric being amplified with the U.S.-Israel war against Iran is associated with beliefs that once Israel is restored as a nation and the temple in Jerusalem is rebuilt, Jesus will return and judge humanity.

Christians adhering to these views read the Biblical Book of Revelation, with its vivid symbolic apocalyptic language, as making literal claims about history. They maintain their inspired and authoritative Biblical interpretation allows them to know that conflicts in the Middle East initiate God’s final act in history, with Trump seen as the dominating and aggressive man who can help usher in God’s violent judgment of his enemies.

Interpretations of Jesus’s death and violence

It’s relevant to consider how some Christian beliefs about Jesus’s death correlate with a willingness to support or justify violence.

Protestant Evangelical theologians, such as J. I. Packer and John Stott, argue that Jesus’s death primarily “paid the penalty” for human sin. They emphasize that God’s holiness requires a payment for this sin. In this framework, God orchestrates the violent death of Jesus to satisfy God’s penal justice to forgive humanity.

Non-evangelical Christians, on the other hand, like 19th-century Congregationalist Horace Bushnell and contemporary Mennonite theologian J. Denny Weaver, understand the death of Jesus as an example of God’s love.

In this interpretation, Jesus doesn’t endure violence to pay a debt to God. Instead, the death of Jesus is more akin to that of a martyr’s tragic death. These theologians reject violence as a condition for forgiveness.

A 2012 debate in the Presbyterian Church (U.S.A.) about a hymn demonstrates this tension, with a proposed change of hymn lyrics from “on that cross, as Jesus died, the wrath of God was satisfied” to “the love of God was magnified.” Ultimately, the authors rejected the proposal.

But the conflict demonstrates that Christians are passionate about their different interpretations of Jesus’s death.

Divine violence in atonement

Researchers have shown that penal atonement beliefs predict a negative association with a sense of responsibility for reducing pain and suffering in the world. This is not surprising when violence is incorporated as redemptive into theological frameworks.

I make a connection in my PhD dissertation between accepting divine violence in the atonement and divine violence in eschatology. Of course, this topic is far more complex and nuanced. Nonetheless, Christians are always going through a process of interpretation and negotiation when it comes to sacred texts.

For example, is Jesus the warrior Christ of Revelation 19 riding a warhorse to go into battle against his enemies or the teacher of peace in Matthew 21 who commands his followers to love their enemies just as God perfectly does?

Biblical interpretation and political beliefs

For those who see violence as a tool for redemption, they are more apt to subvert Jesus’s nonviolent teaching with images found in the Biblical book of Revelation. For those who see violence as incompatible with Christian ethics, they will interpret this allegorically, and with humility, paying attention to signs of God not just in their own lives and “insider” group. These two approaches will also inform political beliefs as well.

Consider a recent social media post by Reformed Baptist theologian and pastor John Piper. The post simply quotes Leviticus 19:34:

“You shall treat the stranger who sojourns with you as the native among you, and you shall love him as yourself, for you were strangers in the land of Egypt: I am the Lord your God.”

Piper was quickly labelled “woke” and pushing an “irresponsible” theology by Trump supporters. American theologan Russell Moore noted years ago:

“Multiple pastors tell me, essentially, the same story about quoting the Sermon on the Mount, parenthetically, in their preaching — ‘turn the other cheek’ — to have someone come up after to say, ‘Where did you get those liberal talking points?’”

A more responsible evangelical theology

I argue Christians should not believe in a God of violent death, but life. Violent atonement and eschatology portrays a God who is not above revenge and a God who leaves most of humanity hopeless.

We are left asking a series of disturbing questions if God is indeed about to end the world with violence. Why does the tone of this theology resemble the tone of empire, which crushes enemies instead of building bridges with them? Why does Jesus, as One Person of the One God, expect his followers to love their enemies — if God the Father ultimately does not?

All Christians in the U.S. and beyond need to reject violent theology as incompatible with the love of God that was magnified on the cross.

Matthew Burkholder is a member of the Liberal Party of Canada.

– ref. Evangelical holy war: Why some Christians think Trump will end the world – https://theconversation.com/evangelical-holy-war-why-some-christians-think-trump-will-end-the-world-277617