‘Trump picks fight with Pope’, was one headline I read this morning. Commentators were saying it was foolhardy, or possibly brave, of the Republican frontrunner to take on Francis during a primary season in which so many Catholics will be casting their votes.

I’m not convinced. This is one fight that Trump didn’t start. Pope Francis was asked, mid-flight from Mexico, about Trump’s plan to build a wall to keep illegal immigrants out of the United States. He replied that anyone who wanted to do that wasn’t a Christian. At which point Trump started fuming about how outrageous it was that his Christian faith should be called into question.

Can you blame him? Trump may be a master opportunist, not least when the subject of his religious convictions is raised, but it’s hard to imagine any politician denounced in this offhand fashion deciding not to hit back.

We need to bear in mind one crucial detail. Francis made his sweeping comment about the incompatibility of wall-building and Christianity without knowing the details of Trump’s proposal. He admitted as much.

In this era of uncontrollable demographic change, it’s increasingly difficult to judge whether any immigration policy is Christian or un-Christian. It’s downright impossible if your judgment is formed without a basic grasp of the facts. So why did the Pope allow himself to be drawn into this debate?

Perhaps because he couldn’t help himself. Whether discussing theology or current affairs, the current successor of Peter enjoys improvising. He is quick to form an opinion on any subject he’s asked about. (In a compendium of unlikely quotes, ‘No comment’ from Pope Francis would be up there with the winning entry from a New Statesman competition: ‘Pull its wings off’ – Mother Teresa.)

At the same time, however, he doesn’t watch television or read newspapers. So who supplies him with information about American politics? My guess is that he relies on the chatter of senior Catholic clergy hostile to the United States and especially the Republican Party, of whom there is no shortage.

Anti-Americanism is Jorge Bergoglio’s abiding political prejudice. Formerly a vehement anti-Communist, he has had an ‘intimate and familial’ encounter with Fidel Castro, the veteran murderer of Catholic priests; he has found a new friend in the Russian Orthodox puppet of an ex-KGB tyrant.

Donald Trump, however, is slapped down as ‘un-Christian’ with a carelessness worthy of Trump’s own philippics.

Admittedly, Francis is not the first modern pope to impose his personal geopolitical worldview on his office. In helping to demolish the Soviet bloc, St John Paul II drew on the experience of decades of ingenious opposition to Poland’s communist rulers.

But any comparison of the anti-Communism of Wojtyla and the anti-Americanism of Bergoglio quickly breaks down. The former was a nuanced and exceedingly well-informed response to monstrous dictatorships. The latter is based on a caricature of the United States – a country that, despite living for three quarters of a century in the Americas, Bergoglio had not visited until last year.

Argentina’s snooty and defensive contempt for America stretches back a long way. It draws on several sources, including the half-baked quasi-fascism of Peronism, the anti-US prejudices of European settlers such as the Pope’s Italian father, and the simplistic rich-North-versus-poor-South economic analysis that swept Latin America in the 1950s.

Unlike Polish anti-Communism, Argentinian anti-Americanism has achieved nothing. And now it has been transplanted to the Vatican by a pope with an alarmingly high estimation of his diplomatic expertise.

To repeat: Pope Francis has a policy of not keeping up with the media, preferring his news to be filtered by a kitchen cabinet of advisers who share (and, arguably, manipulate) his prejudices. As a result, he has a special knack for producing unintended consequences. For example, it’s hard to believe that he wanted his tweaking and goading of the Synod on the Family to have quite such a divisive effect.

His latest outburst is no exception to this trend. Only on person will benefit from it, and that is Donald Trump.