There's now about one attack a day on American bases. The attacks are haphazard, usually a 107mm rocket fired in the general direction of the base. The Afghans who fired the rockets are often still in the area, and US infantry and helicopters quickly move to where the attackers appear to be and there are often firefights. The attackers appear to be Taliban and al Qaeda supporters, which are still common in Afghanistan (perhaps 10-20 percent of the population.)