Flying to Algeria at the start of his landmark tour of Africa on Monday, Pope Leo had a choice. He could ignore Donald Trump’s extraordinary overnight social media tirade against him, or he could tackle it head on.

In the end, he chose the second option, taking the highly unusual step of calling out the Trump White House directly. Speaking to reporters on board the papal plane, the pope said he had “no fear of the Trump administration” and would not be deterred from speaking out “loudly” about the message of God.

“I do not think the message of the Gospel should be abused, as some are doing,” he said, adding, “too many innocent lives have been lost… I believe someone must stand up and say there is a better way.”

Leo’s comments have defined him as the most visible international counterweight to Trump and set up an unprecedented clash between the first American pope and a US president who has launched repeated broadsides against him.

Yet the Chicago-born pontiff, known for his gentle, low-key style, did not pick this fight. Having spent much of his adult life in the Order of St Augustine, whose friars and sisters take vows of poverty, chastity and obedience with a focus on unity and community, his priorities are unity and building bridges.

Rather than coming into his position with a flurry of executive orders or news-making initiatives, the pope has used much of his first year in office listening and making gradual changes. He has also emphasized the importance of multilateral institutions such as the United Nations and respect for international law, at a time when the US president has suggested he is not bound by those norms.

Although he’s a more reserved personality than his predecessor, Pope Francis, the US military operation in Iran has brought out Leo’s inner steel, and a willingness to speak out in forthright terms. He decided to name Trump personally – something popes rarely do. While he has not named other members of the Trump administration, his remarks that “God does not listen to the prayers of those who wage war” appeared to allude to US Defense Secretary Pete Hegseth’s eagerness to frame the conflict in the Middle East in religious terms.

Popes calling for peace and opposing war is not new. Pope John Paul II strongly opposed the 2003 US-led invasion of Iraq. With an American pope, however, things are different. Leo XIV speaks English as his native tongue, something that has not happened since the 12th century, and his words cut through to a US audience, the White House and beyond. Leo is also known in the Vatican for his “poker face” – he has a certain inscrutability that makes him hard to read, and his careful, deliberate style arguably gives his words greater weight.

Pope’s message of peace

While in Africa, Leo has continued to speak out, saying his time on the continent offers a message of peace the world needs to hear. During a peace meeting in Bamenda, Cameroon, Leo delivered a speech that had global ramifications.

“The world is being ravaged by a handful of tyrants, yet it is held together by a multitude of supportive brothers and sisters,” he said.

“Woe to those who manipulate religion and the very name of God for their own military, economic or political gain, dragging that which is sacred into darkness and filth.”

Tensions between the pope and Trump have been bubbling away since before the latest clash. Ahead of the conclave that selected Pope Leo last year, the president caused upset when he posted an AI image of himself as the pontiff. It had echoes of the AI image Trump posted – and later deleted – portraying himself as a Jesus-like figure shortly after attacking the pope. It’s also striking that although the cardinals elected the first American pope in the Catholic Church’s 2,000-year history, Trump has not – as far as the public record shows – had any direct contact with Leo since.

Instead Vice President JD Vance, who became a Catholic in 2019, attended Leo’s inauguration, presenting him with an invitation to visit the United States. The Vatican has said the pope will not visit the US in 2026 and instead plans to spend July 4th – the 250th anniversary of US independence – on the southern Italian island of Lampedusa, which is a major landing point for immigrants. It’s hard to see the pope making a visit home while Trump is president.

On Tuesday, Vance weighed into the row, saying the pope needs to be “careful” when talking about theology and should remember “Just War” theory when talking about the war in Iran.

Vance’s mention of Just War theory is striking. Developed over centuries, the teaching is frequently used by military analysts as an ethical and moral criteria for armed conflict. One of its primary architects is Saint Augustine of Hippo, the spiritual father of the Catholic religious order that Leo belongs to. While in Algeria, the pope paid a personal pilgrimage to the place where Augustine served as a bishop in the late fourth and early fifth centuries, and he has pointed out that people do not see the war in Iran as just.

Vatican News argued in an editorial published a day after Vance’s remarks that in recent decades, Catholic teaching has shown “how increasingly difficult it is to claim that a ‘just war’ exists,” particularly in an “atomic era.”

Editorial Director Andrea Tornielli insisted that Leo XIV, “faced with the madness of escalating conflict and disproportionate spending on rearmament,” is continuing “along the path opened by his predecessors, calling for peace, dialogue, and negotiation with both realism and prophetic clarity.”

‘Empires come and go’

Vance’s criticisms of the pope are likely to be taken more seriously by the Vatican, though. As a Catholic convert, he’s already used a teaching of St Augustine to defend the Trump administration’s immigration crackdown. Leo, meanwhile, has been critical of the treatment of immigrants in the US.

“From the time Vance entered the Church, he has aligned himself with a cadre of extreme right-wing philosophers, theologians, and pundits who claim to be the authentic interpreters of Augustine’s City of God [a major work],” Dawn Eden Goldstein, a Catholic author and academic, told CNN.

She said that Pope Leo’s “undeniable expertise in Augustine’s thought… poses a direct threat to the efforts of the vice president and his post-liberal friends to present themselves to Catholics as authoritative interpreters of the Church’s social and political teachings.”

Leo became pope just a few months after Trump’s re-election as president. Previously, the idea of a pope from the US was deemed impossible because the cardinals would not want to ally the Church with the world’s dominant power. Yet Trump’s return to the White House changed how the cardinals viewed the US on the world stage. It opened the door for them to break with tradition, and the figure of Robert Prevost, with his long experience in Latin America, made him an attractive figure.

The historic decision was not dissimilar to that of the 1978 conclave that elected John Paul II. The first Polish pope, and first non-Italian pontiff in 400 years, was chosen at the height of the Cold War and would go onto play a crucial role in the fall of Communism in Eastern Europe.

“The latest incident reminds me of Harold Macmillan [a former British prime minister] who said that among the three institutions no sensible person should attack is the Vatican,” said Gerard O’Connell, Vatican correspondent for America magazine, a Catholic media outlet, and an experienced observer of church affairs. “I imagine the Vatican will view this through the lens of history, knowing that empires come and go.” (CNN)

Update news