I got to this one via the Moyers speech. The 'Left Behind' delusions are fairly typical of the kinds of delusions that have circulated in American subcultures since the founding of the nation. Monbiot has a pretty good summary of the overall belief system. I don't think Bush himself actually believes he's fighting the Antichrist, but many of his acolytes very much believe he is.
...In the United States, several million people have succumbed to an extraordinary delusion. In the 19th century, two immigrant preachers cobbled together a series of unrelated passages from the Bible to create what appears to be a consistent narrative: Jesus will return to earth when certain preconditions have been met.(4) The first of these was the establishment of a state of Israel. The next involves Israel’s occupation of the rest of its “Biblical lands” (most of the Middle East), and the rebuilding of the Third Temple on the site now occupied by the Dome of the Rock and Al-Aqsa mosques. The legions of the Antichrist will then be deployed against Israel, and their war will lead to a final showdown in the valley of Armageddon. The Jews will either burn or convert to Christianity, and the Messiah will return to earth...In this article Monbiot says the Rapture Index is 144, "just one point below the critical threshold, beyond which the sky will be filled with floating nudists". Today I see it's hit 153. It's risky for prophets to be so specific; wise prophets never make numeric statements.