Jonathan S. Landay says they're back in Afghanistan, with funding from Al Qaeda. (ht War and Piece). Which may explain today's news of a bomb blast killing 4 US soldiers. This is serious, as the US loses international prestige. It's like wearing a "kick me" sign...
You just can't have terrorists in government and expect to defeat them. The US didn't allow the Nazi party in Germany after WWII, or Japanese militarist parties in Tokyo. Or Communist parties to share power in Greece or Latin America during the Cold War. So it seems like it was a big mistake for the Bush administration to force Afghans to accept the Taliban in their government. They obviously used restored political clout to protect terrorist operations.