The US announced that they had killed or captured about half the Taliban/al Qaeda leadership, but that operations in Afghanistan would probably go on for several more years. The US said it regretted civilian casualties, but that American troops would continue aggressive operations. In eastern Afghanistan (where the drug and smuggling gangs are powerful) and in south central Afghanistan (where many of the hard core Taliban came from), the population is heavily armed and many are anti-American.  Firing on American troops is increasingly common. The Afghans don't really want to fight, because most of the US troops involved are commandos. The Afghans don't really want to fight with the commandos, but inflicting casualties in an ambush would bring great prestige to any Afghan who could pull it off. Unfortunately, many of these attacks are launched from areas occupied by civilians.