It is estimated (by foreign troops and officials in the area), that there are at least 600,000 armed men in the country (of some 15 million people.) Perhaps ten percent of these men are on the payroll of some warlord, many of the rest would like to be on someone's payroll, but will turn out for free to oppose foreigners or another tribe entering their area with hostile intentions. Foreigners bringing cash and other goodies are generally welcome. The government would like to disarm a lot of these men, but the majority will fight strenuously to keep their weapons.
About half the 4,000 US troops stationed at Bagram airbase (outside Kabul) have gone home. British Royal Marine Commandos have already arrived and joined US troops in field operations (looking for al Qaeda men or material.)