During the Afghanistan war, there were three friendly incidents involving aircraft, two caused by Air Force aircraft, and one by a Navy warplane. The Navy actually performed most of the bombing missions, and dropped most of the smart bombs, although the air force heavy bombers dropped the most bombs by weight and number. This brings up an important point. The navy has long paid more attention to Close Air Support (dropping bombs close to friendly troops.) This is largely because the U.S. Marines have their own air force, which specializes in direct support of marines on the ground. Marine pilots get more infantry training than any other pilots in the world, and even spend time with ground units during their careers. This attitude spread to navy pilots, who are trained in the same facilities and programs as the marine pilots. This attitude towards Close Air Support is no secret in the aviation community. The air force has long tried to get away from Close Air Support, preferring to let the army provide this service with helicopter gunships. But with the increasing effectiveness of smart bombs, the air force finds itself back in the Close Air Support business. Whether this will result in a change in attitude, to more closely match the one found in the Navy and Marine Corps, remains to be seen.