Of all the dramatic changes history has witnessed since 1945 - the economic miracle in postwar western Europe, the collapse of Communism and now the latest boom and bust - none was more unforeseen than the resurgence of religion. A new "revolt of Islam" was quite unexpected 50 years ago, when secular Arab nationalism seemed the rising force, and when, for that matter, secular Israelis didn't guess that "religious Zionists" would one day make the running in their country.

And yet what may be the most striking and important development is the renewed role of religion in the US, and its political implications. John McCain has tried to negatively associate Barack Obama with Jeremiah Wright, his fire-eating radical pastor (or former pastor), but much less attention has been paid to Sarah Palin's membership of the Assembly Church of God in Wasilla and to her own pastor, Ed Kalnins. When Colin Powell endorsed Obama on Sunday, he said Palin was not yet ready to be president. He might have added that her religious opinions also raised questions about her fitness for high office.

Religion may now be the largest gulf between Europe and the US. Mitt Romney, the Mormon who ran for the Republican nomination, spoke of the empty cathedrals of Europe, and Tony Blair was the oddity among European politicians in his public protestations of faith.

Maybe Blair would be more at home in the US, if not quite at Saddleback, the "evangelical megachurch" in California, where McCain and Obama bared their sinful souls. Obama blamed his early "experiments" with alcohol and drugs on "a certain selfishness", and McCain confessed to his "greatest moral failing" with the end of his first marriage.

And yet, weird and embarrassing as this sounded to Europeans, it would have done so to Americans also not long ago. For Herbert Hoover and Franklin Roosevelt to have taken part in any such event during the 1932 presidential campaign would have seemed quite absurd, or Harry Truman and Thomas Dewey in 1948. Four years later, Dwight Eisenhower had so little religious upbringing that he needed to be discreetly baptised before he reached the White House.

In 1960 religion did become a factor, and earlier this year Romney invoked the memory of John F Kennedy to suggest his own eccentric faith shouldn't be held against him. But that was not comparing like with like. Kennedy was the first Roman Catholic to be elected president, and in a famous speech to protestant pastors in Texas he upheld the principle of the first amendment - the separation of church and state.

But he was only insisting that a man of Catholic affiliation could be as good an American as anyone (something the Bible belt was far from conceding when Al Smith, another Irish Catholic, was running for president only 32 years earlier). What Kennedy did not say was that his career had been inspired by a devotion to Our Lady and the Sacred Heart. If he had, apart from the fact that anyone who knew him would have found it hard to keep a straight face, he would have lost the election.

Nearly half a century later there has been a complete change. Palin's convention speech was held for a time to be the height of feisty wit; but much more revealing is what she and her pastor have said about "the end of days", an idea in which millions of American evangelical Christians sincerely believe. According to Kalnins, the Jewish people must be gathered into the Land of Israel as a preliminary to Armageddon. When that vast conflict comes the Jews will be converted, or possibly annihilated, and it will be followed by the Rapture.

Already Kalnins sees "the storm clouds are gathering" through conflict in the Middle East: "Scripture specifically mentions oil instability as a sign of the Rapture. We're seeing more and more oil wars. The contractions of the fulfilment of prophecies are getting tighter and tighter." And he hopes to witness the Rapture soon. "I'm just looking at the turmoil of the world, Iraq, other places - everywhere people are fighting against Christ," he says. Since Palin is one of his flock, she presumably believes this too. She certainly believes that Jesus told us to invade Iraq: she said so from the pulpit.

Not long ago John McCain was obliged to disown John Hagee, a Texan preacher with a huge following who is not only militantly hostile to Catholicism and Islam but believes that "Hitler was a hunter" who had been sent by God to drive the Jews to Israel. Even assuming that McCain does not become the next president, sceptical Europe might stop and think about where the fulfilment of prophecies could yet lead us all.

wheaty@compuserve.com