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Could a bird flu pandemic spread to humans?

Published

2 years ago

May 10, 2024

Could a bird flu pandemic spread to humans?

The bird flu virus, which was first reported in US poultry farms in 14 states in early 2022, has spread to cows and two humans in the first-ever cases of bird flu in humans in the United States. The same subtype of bird flu is also spreading in other countries, in what experts are calling a “global pandemic for animals”.

US public health officials have been monitoring dairy cow herds, as well as beef and milk products around the country since the first outbreak in cows was reported in March. So far, the US is the only country to have reported bird flu in cattle, but there are fears that it could pose a serious threat to humans, too.

In April, a Texas farm worker contracted the virus in what is believed to be the first-ever transmission of the virus from a mammal – in this case, cattle – to a human. Thankfully, he suffered only mild conjunctivitis – an infection in the eye – and has since made a full recovery. The US’s first-ever bird flu case in a human was reported in 2022 when a poultry farm worker in Colorado was exposed to infected chicken. He reported only fatigue as the main symptom.

However, bird flu can be extremely dangerous for humans. Since the virus – also known as Avian Influenza – was first detected nearly three decades ago in China, some 860 people have been infected by birds in 23 countries, including China, Egypt, Vietnam and Turkey, according to the World Health Organization (WHO). Of those, 463 people died from the virus, giving a huge 52 percent death rate.

So far, the Centres for Disease Control and Prevention (CDC) has detected the virus in more than 200 cows, 9,000 wild birds and some 90 million chickens across the US.

On Friday last week, Canada began implementing stricter import checks for US cattle, following similar measures in Colombia.

So how is bird flu spreading, and could it become a more serious threat to humans?

What is bird flu?

Bird flu is a viral infection that primarily affects birds. Some strains of bird flu can, however, also be infectious to other animals, including humans.

Bird flu belongs to the Influenza A group, one of four types of influenza, and the only one known to cause flu pandemics.

There are also subtypes of avian influenza. Three of these – H5N1, H5N6 and H7N9 – have been found to cause illness in humans as well. While the letters in the names of these subtypes refer to a combination of proteins found in bird flu, the numbers indicate the subtype.

The first and best-known subtype of bird flu is H5N1, which was first identified in domestic geese in the Guangdong province of southern China in 1996. This is the subtype of bird flu which is currently affecting birds and cattle in the US.

In birds, the virus is likely to cause severe disease and death. Cows, particularly older ones, have displayed symptoms such as reduced appetite and lactation when infected.

“This particular strain of the H5N1 virus has been causing a global pandemic for animals – the term is an epizootic disease – and it has affected a lot of domestic poultry production,” said Meghan Davis, associate professor at the Johns Hopkins Bloomberg School of Public Health and trained dairy veterinarian.

How widespread is bird flu among cattle in the US?

Since late March, H5N1 has been reported in around 200 animals in 36 dairy cattle herds in the US states of Colorado, South Dakota, Kansas, Michigan, North Carolina, Idaho, Texas, Ohio and New Mexico.

Some experts suspect that the outbreak may have begun to spread to cows before March – even as early as late 2023 – but was not reported.

“What we don’t know is just how widespread this might be”, said Davis. “This is something where we need lots of surveillance, lots of eyes on this, lots of different ways of looking at the challenge.”

Could bird flu spread to cattle in other countries?

Although there have been no confirmed cases of bird flu in cows beyond US borders so far, the World Health Organization (WHO) has warned that there is a risk of it spreading internationally through the movement of migratory birds.

“With the virus carried around the world by migratory birds, certainly there is a risk for cows in other countries to be getting infected,” said Wenqing Zhang, head of WHO’s Global Influenza Programme, at a news briefing in Geneva in late April.

Dairy cows in their pen at a cattle farm in Rockford, Illinois, US on April 9, 2024 [Jim Vondruska/Reuters]

How dangerous is bird flu for humans?

H5N1 is described by the CDC as “highly pathogenic”, meaning it is “strongly able to cause disease”, in birds. But it has also proved to be deadly to humans in past cases. Only 860 people around the world have contracted the virus since it was first discovered in 1996, but more than half of those have died from it, according to the WHO.

Farm workers or others in direct contact with infected animals are most at risk. Beyond that, humans are unlikely to be able to transmit the virus to each other, although there was one suspected case of human-to-human transmission in Indonesia in 2006.

In humans, bird flu can cause a range of symptoms within two to eight days after infection. This ranges from fever, cough, sore throat and muscle aches, to more severe effects such as pneumonia and organ failure.

How do we treat bird flu in humans?

There is no vaccine for bird flu in humans. Infected people are typically prescribed antiviral medication such as oseltamivir or zanamivir to manage the symptoms. Health authorities including the CDC recommend administering such drugs as soon as symptoms begin.

How do farmers deal with outbreaks of a virus?

In most parts of the world, farmers cull animals which have been exposed to an outbreak of a deadly virus such as bird flu. Early in April, for example, a poultry farm in Texas destroyed 1.5 million chickens to curtail the spread of bird flu.

So far, there have been no reports of cattle being culled. This is because bird flu has so far not been as deadly in cows as it has in chickens and turkeys, said Andrew Stevens, assistant professor of agricultural and applied economics at the University of Wisconsin-Madison.

“In this setting, culling would be an extreme and costly step to prevent further spread of the disease. This is especially true because we don’t yet have as good a sense of how contagious the bird flu virus is between cattle,” he said.

How is bird flu transmitted to farm animals and humans?

Bird flu can be spread by wild birds and waterfowl such as ducks and geese through their droppings or secretions such as saliva.

When poultry or other animals scavenge environments which have been contaminated or have come into contact with infected birds, they can catch the virus too. Infected wild birds may also be present on farms and come into contact with water or feed that cows consume, although researchers are still studying such potential modes of transmission, said Davis.

In cattle, it is still not fully understood how the virus passes from one cow to another, but traces of the virus in milk suggest a heavy viral load can often be found in the mammary glands. Higher viral load in milk compared with respiratory tracts of cows may also point to the routes of exposure of the virus.

Scientists suspect, therefore, that the virus spreads when cows are milked, as equipment may become infected or the virus may become aerosolised – suspended in the air – during cleaning.

Humans who have close or prolonged contact with farm animals or wild birds can become infected when the virus enters their system via the eyes or mouth, or when droplets or small aerosol particles are inhaled via the nose.

Can you contract bird flu from milk and beef products?

Since April, the US Food and Drug Administration (FDA) has tested 297 milk products, including milk, cottage cheese and sour cream. Traces of the virus were found in 20 percent of an initial 96 samples but additional testing has confirmed that pasteurisation – a heating process used by farmers to screen out harmful pathogens and bacteria from farm products – kills the virus, removing the danger for consumers.

Experts and public health authorities including the CDC strongly advise people to only consume pasteurised dairy products, not just because of avian flu but also to avoid bacterial infections such as salmonella and brucella.

Beef samples tested by the US Department of Agriculture (USDA) have so far tested negative for bird flu, but official advice from the FDA remains against consuming raw beef.

Aren’t all dairy products pasteurised?

There is a growing movement against food regulation, seen by some in Western countries such as the US as a symbol of freedom. In 2015, for example, Wyoming passed the Food Freedom Act which allows farmers to sell raw milk and other farm goods directly to customers.

Australia, the only country apart from Canada with a blanket ban on raw milk sales, also has a growing “Raw Milk Movement” which advocates for regulated distribution of unpasteurised products. Such regulations would include hygienic production and packaging of the milk, as well as testing for active harmful pathogens.

While 30 US states allow sales of raw milk, federal law prohibits the distribution of unpasteurised milk across state lines. Additionally, milk from sick cows must be discarded completely under federal law. In cases where raw milk has been packaged before cows are found to be ill, however, products with traces of the virus could still make it to store shelves.

Although such a study has not been conducted on humans due to research ethics, US studies of cats which consumed raw milk infected with H5N1 showed that the cats became sick or even died as a result.

How are the authorities in the US responding to the bird flu outbreak?

Experts and public health authorities such as the CDC say they have been studying bird flu for decades now, and that the COVID-19 pandemic has led to positive shifts in terms of preparing for outbreaks.

Regulatory authorities are also stepping up surveillance of viruses. In late April, the USDA began to require all dairy cattle moving between states to be tested for bird flu.

However, testing at farms within state boundaries is still only done on a voluntary basis, which may not be enough to curb the spread of the virus, said Davis.

“What I would like to see happen is a switch from what we would consider to be more passive surveillance where we are waiting on farmers and workers to tell us that they’re having a problem, to a more active surveillance where we’re really trying to understand the scope of the problem,” she said.

One way to do this is through antibody serology testing, she said, whereby samples of blood or saliva are taken from a human and tested to detect whether their immune system has been exposed to the virus recently.

Another form of testing is polymerase chain reaction (PCR) testing, which typically uses more invasive nasal swabs to determine if a person is currently infected and may not be best suited for those who are asymptomatic or have not had very high exposure to a virus, said Davis.

Rural populations in the US may especially be at a disadvantage during the outbreak, as they can lack access to healthcare services and personal protective equipment, she added. Medical centres may be far away and these populations may be unable to afford services. “And if they [farmers] are not interested in having cows tested, then would the workforce even have the opportunity to get tested? That’s unclear,” she said.

How are other countries reacting to the US bird flu crisis?

In late April, Colombia became the first country to limit trade with the US because of bird flu in cows. It has restricted imports of beef and beef products from states where cows have tested positive for the virus.

Mexico, a major market for US beef and dairy products, has also increased surveillance of cattle entering the country for any sign of respiratory distress, the agriculture ministry said.

On Friday last week, the Canadian Food Inspection Agency also tightened import controls relating to US cattle, introducing a requirement for exporters to provide negative bird flu test results for lactating dairy cattle as well as mandatory testing of retail milk to check for traces of the virus.

Stevens said such measures are important for the long-term sustainability of supply chains. “Although increasing import checks of cattle and dairy products from the US may slightly increase the relative costs of US exports, these costs are small relative to the potential impacts of an import ban or moratorium.”

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Madonna Teams Up With Sabrina Carpenter at Coachella for Transcendent Duets: ‘Vogue,’ ‘Like a Prayer’ and New Song

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1 hour ago

April 18, 2026

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Madonna Teams Up With Sabrina Carpenter at Coachella for Transcendent Duets: ‘Vogue,’ ‘Like a Prayer’ and New Song

After rumors swirled that she would appear at Coachella weekend one, Madonna made a cameo during Sabrina Carpenter’s headlining performance on Friday night, emerging near the end of the set to perform “Vogue,” “Like a Prayer” and a new duet.

Carpenter was midway through “Juno” — typically the song on her “Short ‘n Sweet” tour where she’d “arrest” a different celebrity — to bring out Madonna. The pop queen emerged through the middle of the stage to sing “Vogue,” joining Carpenter to debut a new duet that’s rumored to be on the singer’s upcoming album “Confessions II.” Then, Madonna took the mic to give an extended address to the audience.

“So 20 years ago today I performed at Coachella,” said Madonna. “I was in the dance tent and it was the first time I performed ‘Confessions on a Dance Floor Pt. 1’ in America, and that was such a thrill for me, so you can imagine what a thrill it is to be back 20 years later in the same boots, with the same corset, the jacket I had on earlier, a Gucci jacket. So it’s like a full circle moment, you know? Very meaningful for me.”

After Madonna gave an astrology lesson (literally), the two joined forces to duet on her classic “Like a Prayer,” with backup dancers dressed in habits sauntering down from the back of the stage. “The great thing about music is that it brings people together. Am I right?” said Madonna. “It’s the one place that people have to put their differences aside. Put their shit down and everyone just have a good time togehter, right? So I am thrilled to be a part of that healing experience of bringing people together. I just want to say, four lines from my ‘Confessions 1’ record. It goes like this. Can we get together? I really, I really want to be with you. Come on check it out with me, I hope you, I hope you feel the same way too.”

As she said, Madonna’s appearance during Carpenter’s set comes 20 years after her Coachella debut in 2006, when she popped up at the Sahara Tent instead of the main stage to perform cuts from “Confessions on a Dance Floor.” She later returned to the desert for a surprise cameo during Drake’s closing set in 2015, singing “Human Nature” and “Hung Up” and, in one of the most talked-about moments that year, kissed Drake.

The timing of Madonna’s return to Coachella aligns with the announcement of her upcoming album “Confessions II” earlier this week. The project, slated for July 3 via Warner Records, marks her first full-length album in seven years and her reunion with Stuart Price, the producer of the original “Confessions on a Dance Floor.” Earlier on Friday, Madonna premiered the song “I Feel So Free” on iHeartRadio’s Pride Radio, giving a first taste of the project.

Leading up to her Coachella performance last weekend, Carpenter dropped the video for “House Tour,” the latest single off of last year’s “Man’s Best Friend.” In the clip, she has a girls’ night out with Margaret Qualley and Madelyn Cline, ransacking a stranger’s house and stealing a Grammy.

Carpenter previously performed at Coachella in 2024, foreshadowing that she’d one day take top billing during a custom outro for “Nonsense”: “Made his knees so weak he had to spread mine / He’s drinking my bathwater like it’s red wine / Coachella, see you back here when I headline.” This year’s headlining gig comes after a busy few years for the singer, who kicked off her “Short ‘n Sweet” tour — her first arena trek — in September 2024. She stayed on the road through the end of 2025, when she closed the tour with six nights at Los Angeles’ Crypto.com Arena just a week before she was celebrated as Variety‘s Hitmaker of the Year.

World

Trump’s favorite field marshal: Who is Pakistan’s powerful army chief Asim Munir with deep intel ties

Published

2 hours ago

April 18, 2026

Press Room

Trump’s favorite field marshal: Who is Pakistan’s powerful army chief Asim Munir with deep intel ties

Mark Dubowitz says Trump holds ‘maximum leverage’ over Iran as ceasefire begins

Mark Dubowitz, CEO of the Foundation for Defense of Democracies, analyzes President Trump’s firm Iran policy following a two-week ceasefire agreement. He highlights the regime’s weakened state after 15 months of Trump’s administration, making Iran’s 10-point peace plan with “ridiculous demands” unlikely to be accepted. Dubowitz discusses the choice facing Iran’s new regime.

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President Donald Trump publicly thanked what he called Pakistan’s “great prime minister and field marshal, two fantastic people!!!” in a Truth Social post Friday praising Prime Minister Shehbaz Sharif and Pakistan’s military chief, Asim Munir.

Sharif quickly responded on X, “On behalf of the people of Pakistan, Field Marshal Syed Asim Munir, and on my behalf, I express my deep and profound appreciation for your kind and gracious words.”

The public exchange capped a remarkable rise for Munir, who has become one of the few foreign officials trusted both by Trump and by Iran’s security establishment.

TRUMP AGREES TO 2-WEEK CEASEFIRE IF IRAN OPENS STRAIT OF HORMUZ

In this photo released by the Inter Services Public Relations, Pakistan’s Chief of Defense Forces and Army Chief Gen. Asim Munir, center, Pakistan Naval Chief Admiral Naveed Ashraf, left, and Pakistan Air Force Chief Air Chief Marshal Zaheer Ahmed Babar attend a guard of honor ceremony at the joint military command headquarters in Rawalpindi, Pakistan, Monday, Dec. 8, 2025. (Inter Services Public Relations via AP)

Munir recently became the first foreign military leader to visit Iran since the latest escalation between the United States and Iran, according to Pakistani and Iranian reports. Arriving in full military uniform, he was warmly greeted by Iranian Foreign Minister Abbas Araghchi and held meetings with senior Iranian military officials.

Retired Pakistani Gen. Ahmed Saeed told Fox News Digital that Munir has for months served as an informal back channel between Washington and Tehran, Iran, as the Trump administration tries to negotiate an end to the conflict, Iran’s nuclear program and the naval blockade in the Persian Gulf.

Few foreign figures appear to have closer ties both to Trump and to Iran’s military hierarchy.

That has raised a striking question: How did the same man become close both to Trump and to some of Iran’s most powerful commanders?

Saeed, who said he has known Munir personally for years, told Fox News Digital that Munir began building ties with Iran while serving as Pakistan’s director general of military intelligence in 2016 and 2017.

“He has been interacting with the leadership. He has been interacting with the intelligence community. He has been interacting with the IRGC,” or the Islamic Revolutionary Guard Corps, Saeed said.

According to Saeed, Munir built ties not only with the Islamic Revolutionary Guard Corps but also with Iran’s regular army and intelligence apparatus. Saeed said Munir had longstanding contact with former Islamic Revolutionary Guard Corps Quds Force commander Qassem Soleimani, who was killed in a U.S. strike in 2020, commander Hossein Salami, who was killed in an Israeli strike in June 2025, and other Iranian military figures.

JD VANCE SAYS THE BALL IS ‘IN IRAN’S COURT’ AFTER PAKISTAN PEACE TALKS STALL

Few foreign figures appear to have closer ties both to Trump and to Iran’s military hierarchy. (Iranian Presidency / Handout/Anadolu via Getty Images)

“He continues to be a figure internationally who has personal interactions, a personal equation in the intelligence community in Iran, in the military hierarchy in Iran, in the diplomatic corps of Iran and also on the side of the political leadership,” Saeed said.

That longstanding relationship appears to explain why Iran welcomed him so warmly, even as he remains in direct contact with Trump and his team.

Foundation for Defense of Democracies’ Bill Roggio told Fox News Digital that, “Trump should not trust the Pakistanis. Pakistan was a perfidious ‘ally’ in Afghanistan, backing the Taliban while pretending to be our friends. Munir’s ties to the IRGC should be a massive red flag for the Trump admin.”

Munir’s relationship with Trump dates back to the India–Pakistan crisis of May 2025. Munir played a key role in helping de-escalate the confrontation, and afterward Pakistan formally nominated Trump for the Nobel Peace Prize, a move widely viewed by Pakistani analysts as encouraged by Munir.

Pakistan’s Asim Munir has become one of the few foreign officials trusted by both President Donald Trump and Iran’s security establishment, according to Pakistani analysts and officials. (Jacquelyn Martin / POOL / AFP via Getty Images)

Since then, Trump repeatedly has praised him. Trump has called Munir an “exceptional man,” a “great fighter” and “my favorite field marshal.”

Pakistani officials and media reports say the two men now speak directly.

Pakistani analyst Raza Rumi told Fox News Digital that Munir’s appeal to Trump is not surprising.

“Trump has long shown a preference for strong, decisive leaders,” Rumi said. “Munir fits that mold as a centralized authority figure who can deliver outcomes.”

WHY TRUMP, IRAN SEEM LIGHT-YEARS APART ON ANY POSSIBLE DEAL TO END THE WAR

Iran’s Parliament Speaker Mohammad Bagher Qalibaf and Foreign Minister Abbas Araghchi were greeted by Pakistan Foreign Minister Ishaq Dar and Army Chief Field Marshal Gen. Asim Munir upon their arrival at Nur Khan airbase in Rawalpindi, Pakistan, April 11, 2026. (Pakistan Ministry of Foreign Affairs/AP)

Rumi described Munir as “a disciplined, institution-first leader with a strong emphasis on order, hierarchy and strategic clarity.”

“Unlike more publicly charismatic military figures, his style is relatively understated, shaped by intelligence work and operational experience rather than overt political signaling,” Rumi said.

Munir’s background helps explain both his style and his influence.

Munir studied at the Fuji School in Japan, the Command and Staff College in Quetta, the Malaysian Armed Forces College in Kuala Lumpur, and Pakistan’s National Defence University, where he earned an master of philosophy degree n public policy and strategic security management, according to Pakistan’s Geo News. Munir was the first army chief in Pakistan to receive the Sword of Honour, the military’s highest distinction for a cadet. The outlet also described him as an avid reader, traveler and sportsman.

Munir is also a Hafiz-e-Quran, meaning he has memorized the entire Quran by heart.

A former head of both Pakistan’s Military Intelligence and Inter-Services Intelligence agencies, Munir spent years overseeing Pakistan’s most sensitive regional relationships, including with Iran, Afghanistan and India.

TRUMP AGREES TO 2-WEEK CEASEFIRE IF IRAN OPENS STRAIT OF HORMUZ

Vice President JD Vance shakes hands with Pakistani Deputy Prime Minister and Foreign Minister Mohammad Ishaq Dar in Islamabad on April 12, 2026, after talks on Iran. Pakistan’s Interior Minister Mohsin Naqvi, Chief of Defence Forces Chief of Army Staff Field Marshall Asim Munir, and U.S. Embassy Charge d’Affaires Natalie A. Baker look on as Vance prepares to board Air Force Two. (Jacquelyn Martin/AP)

In 2025, after the India-Pakistan crisis, he was elevated to field marshal, the first Pakistani officer to hold the rank since former military ruler Ayub Khan.

Pakistani officials say that later that year, he also was given the newly created title of chief of defense forces, further cementing his authority above the country’s military branches.

Munir rarely gives interviews, but his speeches offer clues to his worldview.

WHO ACTUALLY RUNS IRAN RIGHT NOW? THE KEY POWER PLAYERS AS TRUMP CLAIMS TALKS TO ‘TOP’ OFFICIAL

At the Margalla Dialogue in Islamabad in November 2024, he warned that “absence of proper regulations for freedom of expression is leading to the deterioration of moral values in societies worldwide.”

The remark reflected a broader emphasis on order, discipline and centralized authority.

Rumi said Munir operates from “a transactional, state-centric worldview rather than an ideological one.”

Yet critics argue that his rise has come at a cost to Pakistan’s democracy.

After becoming army chief in 2022, Munir focused heavily on domestic politics, including what critics described as a crackdown on political opposition and an unprecedented concentration of military power, according to The Guardian, which reported that key negotiations with the United States and Iran have been coordinated not from Islamabad, Pakistan’s civilian capital, but from Rawalpindi, the headquarters of the military.

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A broken frame of Pakistan’s field marshal and army chief, Asim Munir, hangs on the wall after an attack at the Cadet College Wana, a military-linked school, in the South Waziristan district near the Pakistan-Afghanistan border, Nov. 13, 2025. (Aamir Qureshi / AFP via Getty Images)

Critics say that reflects a broader reality: Pakistan’s foreign policy is increasingly being run by the army rather than the elected government.

Rumi said Munir’s rise reflects “the military increasingly eclipsing civilian leadership in Pakistan.”

As the current negotiations continue, much appears to rest on Munir. Saeed said that is because Munir has spent years building trust on both sides and is unlikely to stop now.

“Knowing our field marshal, and from my own personal knowledge of him, he is relentless. He would not give up,” Saeed said.

Efrat Lachter is a foreign correspondent for Fox News Digital covering international affairs and the United Nations. Follow her on X @efratlachter. Stories can be sent to efrat.lachter@fox.com.

World

White House vs the pope: What is behind the Catholic just war doctrine

Published

3 hours ago

April 18, 2026

Press Room

White House vs the pope: What is behind the Catholic just war doctrine

When US Vice President JD Vance converted to Catholicism in 2019, he chose Saint Augustine as his patron.

On Tuesday, speaking at a Turning Point USA event, Vance invoked the tradition of the fifth-century theologian and one of the most important Church fathers to push back against Pope Leo XIV’s criticism of the war in Iran.

The White House number two warned the pontiff to “be careful when he talks about matters of theology,” citing “more than a 1,000-year tradition of just war theory” in his defence.

Meanwhile, the supreme pontiff of the Catholic Church was in the Algerian port city of Annaba, paying homage at the basilica not far from where St Augustine died and was initially interred.

Hippo Regius, as it was known in the bishop’s time, is where St Augustine wrote most of what became the intellectual basis of the just war principles Vance was claiming to defend. Pope Leo XIV is the first pontiff to hail from the Augustinian order.

Whether Vance knew what the Holy Father’s itinerary was that day, his office did not say.

Vance was not the first member of the administration to weigh in.

Days earlier, US President Donald Trump had posted on Truth Social and later reiterated to the press that Pope Leo XIV was “weak on crime” and “terrible for foreign policy,” suggesting the pontiff believed Tehran should be allowed to develop nuclear weapons.

The pope never made any comments regarding the Islamic Republic’s right to nukes.

The post came after the pope had called Trump’s threat to destroy Iran’s “whole civilisation” “truly unacceptable”.

Pope Leo XIV responded the following morning on board the papal plane to Algiers. “I’m not afraid of the Trump administration or of speaking out loudly about the message of the Gospel,” he said.

“I will continue to speak out loudly against war, looking to promote peace, promoting dialogue and multilateral relationships among the states to look for just solutions to problems.”

What the doctrine says

Just war theory, rooted in St Augustine and further elaborated on by Thomas Aquinas in his Summa Theologiae, sets out strict conditions for the moral use of military force.

The threat must be lasting, grave and certain, and success must be realistically achievable. Most importantly, all other means of resolution must be genuinely exhausted, and the harm caused must not exceed the harm it seeks to prevent.

Put simply, the purpose of this set of rules is to prevent those engaged in war from being the final judges of their own righteousness.

“The just war doctrine doesn’t merely ask whether your cause feels just,” Joseph Capizzi, Dean of the School of Theology and Religious Studies at the Catholic University of America, told Euronews. “As we all know, everybody thinks their situation is just.”

“It understands that most people think of their causes as just. But it is a means by which you can distinguish legitimately just causes of war from illegitimate causes of war.”

The doctrine has also shifted in how it is applied. For most of its history, it was used by priests to authorise their rulers’ wars. Spurred on by world wars and the discovery of nuclear weapons, the modern papacy has used it in the other direction.

“Before, just war doctrine was used often by national clergy to give permission to their emperor or their king to go to war,” Massimo Faggioli, professor of ecclesiology at Trinity College Dublin told Euronews.

“Right now, it is used mostly — I would say almost always — to say ‘well, no, this military intervention doesn’t meet those criteria.’”

Writing as the Roman Empire crumbled, St Augustine had already posed the question of what is righteous in one of the most well-known open checks on power in Catholic moral thought.

“Justice removed,” he asked in The City of God, “what are kingdoms but great bands of robbers?”

Vance has cited The City of God as “the best criticism of our modern age” he has ever read, deeply affecting his religious outlook and thoughts on domestic and foreign policy.

Vatican’s track record

The administration’s framing of Pope Leo XIV as a pacifist who simply does not understand that force is sometimes necessary contradicts the pontiff’s and the Church’s track record, experts say.

Before his election just last year, the pontiff was a registered Republican voter. While he has criticised the Iran war, the Holy Father has shown support for Ukraine’s right to self-defence.

In recent decades, past popes also carefully deliberated the context before commenting on any given conflict.

The Holy See quietly regarded the post-September 11 intervention in Afghanistan as meeting just war criteria, as the US went after Taliban extremists and Al-Qaeda’s Osama bin Laden.

Yet Pope John Paul II opposed both the 1991 Gulf War and 2003 invasion of Iraq not as a pacifist, but on the grounds that last resort had not been demonstrated. Pope Leo XIV’s position on Iran is in line with his predecessors, according to theologians.

“To accuse the pope of being a pacifist is really absurd,” Faggioli said. “Vance and Trump are accusing the pope of thinking about war like a European Catholic. But that’s not true.”

“He is using just war doctrine — and the American cardinals who have spoken against the war in Iran, they have used just war doctrine in ways that Europeans would not. So this is, in some sense, an intra-American debate.”

There is also the matter of what Vance actually said — not just about just war, but about the pope’s remit, after he suggested Pope Leo XIV should confine himself to morality and stay out of foreign policy, Faggioli explained.

“Vance is one of those typical Catholics who thinks that morality is only sexual morality,” Faggioli said. “When he said the pope should stick only to morality, he meant sexual morality — as if war were not a matter of morality. Of course it is.”

Thousand-year tradition and its tenets

The US bishops and other Catholic Church clergy indeed did not stay quiet. On Wednesday, Chairman of the USCCB Committee on Doctrine Bishop James Massa issued a statement in support of the Holy Father’s position, but also the Catholic Church as a whole.

“A constant tenet of that thousand-year tradition is a nation can only legitimately take up the sword ‘in self-defence, once all peace efforts have failed,’” Massa, auxiliary bishop of Brooklyn, wrote.

“When Pope Leo XIV speaks as supreme pastor of the universal Church, he is not merely offering opinions on theology. He is preaching the Gospel and exercising his ministry as the Vicar of Christ.”

Unlike in other public exchanges in recent times with those opposing Washington’s view, the Trump administration has struggled to find the usual levers, experts say. “It’s very hard for them to use the usual tactics to delegitimise the pope, because he is American,” Faggioli said.

“They can’t call him a communist, they can’t call him a radical leftist — his record as a theologian doesn’t support that.”

Euronews contacted several Catholic institutions and theologians for perspectives to further outline the Trump administration’s application of just war doctrine, but none agreed to speak on the record.

‘A consistent lesson of our faith’

On Thursday, from a peace meeting in Cameroon — a country not without its own existing tensions — the pope said, “Woe to those who manipulate religion and the very name of God for their own military, economic, and political gain, dragging that which is sacred into darkness and filth.”

The post on X from his official Pontifex account drew nearly 10 million views in English alone by Friday evening.

Capizzi urged against reading every papal statement as aimed at Washington, however. “You’re in Cameroon, on a continent marked by severe religious conflict; that comment has a much broader application.”

Still, according to Capizzi, the Holy Father’s words are meant for all of the faithful.

“Any believer who appeals to God — as though God is on their side — ought to do so with great fear and trembling,” he said. “That is a consistent lesson of our faith: that a believer is the person who has a healthy fear of God and of God’s judgment of his or her actions. And that includes the way he or she speaks about God.”

The same day at the Pentagon, US Secretary of Defence Pete Hegseth led a worship service and read what he described as a prayer recited by Combat Search and Rescue crews during the Iran operation.

He introduced it as “CSAR 25:17,” meant to reflect Ezekiel 25:17. What followed was nearly verbatim the monologue delivered by Samuel L Jackson’s hitman in Quentin Tarantino’s Pulp Fiction, in the scene immediately before his character Jules Winnfield commits a murder.

The actual Ezekiel 25:17 is considerably shorter and less specific. Tarantino’s version was itself adapted from a 1973 Japanese martial arts film.

‘Nothing against the pope’

Trump won around 55% of US Catholic votes in 2024. A poll conducted in late March, jointly by Republican pollster Shaw & Co Research and Democratic pollster Beacon Research, found his approval among Catholics had fallen to 48%, with 52% disapproving.

A Fox News poll found US Catholics opposed to military action in Iran by 10 points and against Trump’s conduct toward Iran by 20. A separate NBC survey found US registered voters now view the pope more favourably than the president by a net margin of 46 points.

On Thursday, Trump told reporters he has “nothing against the pope” and is “all about the Gospel,” while continuing to state Pope Leo XIV was in favour of Tehran having nuclear weapons.

Trump also said his preference remained with the pope’s brother Louis, who lives in Florida. “Louis is all MAGA. He gets it, and Leo (XIV) doesn’t,” Trump said.

“If I wasn’t in the White House, Leo wouldn’t be in the Vatican,” he reiterated.

The night before, police had surrounded the New Lenox home of a different brother of the pope, John Prevost, following a bomb threat. K9 explosive-detection units found nothing. The investigation remains ongoing.

The greater picture

For Faggioli, the dispute is a symptom of something that has been building for years: not a domestic row about one war, but a contest over what Christianity means and who speaks for it.

“America always had a religious understanding of itself as a nation, but presidents were very cautious about not looking like messianic figures — at least in life,” Faggioli said.

“Trump has exploited the creation of a vacuum of secularisation in America, and he has filled that vacuum with a certain degree of messianism — and some American Christians are happy about that.”

“Trumpism is a form of political messianism. He sees himself — and many people see in him — someone with a divine mission: a political Messiah who will deliver salvation to America, to Americans, to Christianity. And he is serious when he posts those things.”

Capizzi, for his part, was more of the belief that the US president would eventually mend bridges with the Holy See. “I actually consider this a hopeful sign — that it’s touching and impacting President Trump, despite what he’s saying and what he’s posted.”

“This conversation has shown that the Church retains her moral authority,” he said.

“This is a teaching moment. Catholics and others are getting to see that these doctrines are over a thousand years old, that we have thought about these questions for a very long time, and there is a moral gravity behind these claims.”

As for the pope, John Prevost said something crucial about his brother before any of this began. “I don’t think he’ll stay quiet for too long if he has something to say,” he told the New York Times last year. “He won’t just sit back.”