Yikes -- UPI reports:

Iran massing troops on Iraq border

Iran reportedly is readying troops to move into Iraq if U.S. troops pull out, leaving a security vacuum.

The Saudi daily Al-Sharq al-Awsat, monitored in Beirut, reports Iran has massed four battalions at the border.

Al-Sharq al-Awsat quoted "reliable Iraqi sources" as saying, "Iran moved part of its regular military forces towards the Iraqi border in the southern sector at a time its military intelligence agents were operating inside Iraqi territory."

Is this believable? I have no idea. But hey, maybe Matthew Yglesias was on to something when he said Bush might be a mole working for the Iranians....