One third of America's 50 million evangelical Christians believe that the nation of Israel will play a central role in an unfolding end-time theology, polls show.

The details differ, but all the apocalyptic scenarios envision a cataclysmic series of events and the return of the biblical messiah.

Jews will return to Israel, an Antichrist will rise to rule the world, the battle of Armageddon will ensue and Jesus will return to defeat evil and preside over Judgment Day.

In his best-selling book, Jerusalem Countdown, San Antonio pastor John Hagee predicts a battle "that will usher in the end of the world" and plunge the Middle East into "a sea of human blood."

End-time prophesies have seen the enemy in various forms: Hitler, Russia, Saddam Hussein and, now, Iran.

Politically, Mr. Hagee is urging evangelicals to take a hard line against Iran and its nascent nuclear program as part of the war on Islamic extremism.

When President Bush was asked this month about Iran, he said, "I've told people that if you're interested in avoiding World War III, it seems like you ought to be interested in preventing them [Iran] from having the knowledge necessary to make a nuclear weapon."

For believers, it was an answer that resonated with both political and theological meaning.