That armed militias in the midwest were preparing for an actual battle with agents of the Antichrist is not a surprise. Fear mongering has become epidemic on the political right. Why now? Since the millennium comes at the end of the Tribulations, its approach is constantly expected, and not necessarily tied to any specific date. So warnings that Obama is either the Antichrist or in service to the Satanic plan to build a New World Order are taken seriously by some fundamentalist Christians.
The apocalyptic starting gun for the race to prepare for a battle with the Antichrist was fired in 1970 by Hal Lindsey whose book The Late Great Planet Earth has sold over 19 million copies. Lindsey argued that the end times had arrived and that Christians should watch for the signs of the times. While not all fundamentalists agreed with his specific analysis of Biblical prophecy, a significant number agree that the end times have either begun or are imminent.
The mainstreaming of millennialism received a major boost when, in 1983, Ronald Reagan cited scriptural authority to demonize the Soviet Union as an evil empire. Sara Diamond wrote of the influence of apocalyptic thinking on the new Christian Right in her prescient 1989 book, Spiritual Warfare. In her study The Religious Right and Israel: The Politics of Armageddon, Ruth W. Mouly showed how certain sectors of the Christian right mobilized tremendous support for the State of Israel during the Reagan Administration, in part because they believed Jews had to return to Israel before the prophecies of Revelation could be fulfilled.
Lamy argues that millennialism has many sources, but generally can be tied to societal conflict and resistance to change. On the other hand, Fuller argues that apocalyptic fervor is complex, and part of a "literary and theological tradition," that is "transmitted through a variety of cultural institutions that are relatively immune" to certain "social or economic forces."
http://www.talk2action.org/story/2010/3/29/1470/71194