There are still plenty of guns and explosives in Iraq, as well as older Russian SAM-7 shoulder fired anti-aircraft missiles. Several of these have been fired at American aircraft, but none have hit and all appear to have been defective. Over a hundred of these SAM-7s have been captured in raids. There are thousands of young Sunni Arabs who are potential recruits for these anti-American groups, as the Americans are seen as the reason for their dim economic prospects. Saddam favored the Sunni Arabs, and his government was the main source of good jobs for young Sunnis over the last two decades. With Saddam gone, many young Sunnis are mad enough to fight, especially if there is some money in it for them. As long as the Baath Party has lots of cash, and there are lots of unemployed Sunni Arabs, the attacks will continue.
The coalition appears to be adopting the same kind of pacification tactics used by the British in Malaysia in the late 1940s, and the Army and Marines in several insurgencies between 1898 and 1934. This method concentrates on policing, not only to suppress normal criminal activity, but also to prevent armed groups that seek to use terror to obtain control over civilian populations. Without voluntary or coerced cooperation from Sunni civilians, the armed groups will eventually be identified and put out of business. But it can take a year or more to install an effective police and courts system. The United States has been recruiting police and judicial experts to serve in Iraq, and sending lots of Military Police units as well.
Attacks against American troops are down to about 12 a day. The attackers are changing their tactics as the Americans have developed patrol and convoy techniques that amount to rolling ambushes. As a result, more attackers are being killed or captured. Non-Iraqis are often among the prisoners, and interrogations indicate an unorganized resistance driven partly by money, partly by a desire for Sunni Arabs to regain control of the country and partly by hatred of non-Moslems. The new enemy tactics favor long range (up to 300 meters) shots with RPGs and improvised mines (remote controlled explosives.) Most attacks are at night.