One year after the death of Pope Francis, the Vatican this week hosted the premiere of a documentary tribute by Martin Scorsese. For a pontiff whose charisma and crowd-pleasing style helped cut through to a secular audience, marking the anniversary with the help of one of the world’s most famous film directors was a nice touch.

Francis’s successor, Leo XIV, is a far less flamboyant personality. In his inaugural year in St Peter’s chair, the first pope to come from the United States has generally taken a cautious, circumspect approach to his role. But it turns out that an aura of mildness and restraint makes him no less effective when criticising the posturing that passes for Christian piety in Donald Trump’s Washington.

Francis clashed fiercely with Mr Trump over immigration and the climate emergency. Famously, he also took on JD Vance regarding St Augustine’s theory of love, which was misused and manipulated by the Catholic vice-president to justify demolishing the US aid budget. A blunt pontifical letter to US bishops, clearly written with Mr Vance in mind, pointed him in the direction of the parable of the Good Samaritan and “the love that builds a fraternity open to all”.

Pope Leo’s rebukes during Mr Trump’s illegal war in Iran have been similarly trenchant, taking aim at the style and substance of Washington’s apocalyptic rhetoric and reckless actions. After the US secretary of defence, Pete Hegseth, an evangelical Christian, requested that US citizens pray for victory in Iran “in the name of Jesus Christ”, the pope delivered a homily stating that Jesus “does not listen to the prayers of those who wage wars. He rejects them.” He subsequently told reporters: “I do not think the message of the gospel should be abused, as some are doing … too many innocent lives have been lost.”

Mr Trump’s needled response has included trademark abuse on his Truth Social site (the pope has drily pointed out the irony of the name), the posting of an egregious AI image depicting himself as a Christ-like saviour, and the public reading of a supposedly Maga-friendly passage from the Old Testament. The US president appears to imagine God as just another strongman, albeit one armed with an eternal mandate. But falling poll ratings among US Catholics, and disapproval from the likes of Italy’s Catholic prime minister, Giorgia Meloni, suggest that the Chicago-born pope is winning the argument.

Given the influence of Christian nationalism in the rise of the Maga movement, that could be a significant turn of events. More broadly, in a world where universal values are being eclipsed by the aggressive pursuit of national self-interest, Pope Leo is using his influence to provide a much-needed moral counterweight. Illiberal forces have steadily undermined international norms and institutions intended to protect the weak from the strong. The reach of the Catholic church as a global institution offers a powerful platform for resistance.

One of the great achievements of Francis’s papacy was to see this and take up the challenge, whether in relation to defending the rights of asylum seekers or highlighting the climate emergency. Reflecting on his predecessor’s impact, Pope Leo said this week that “his memory remains vivid in the church and throughout the world”. The world can be grateful that Leo appears determined to follow in Francis’s footsteps.

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