Maj. Dethlefsen was 1 of a flight of F-105 aircraft engaged in a fire suppression mission designed to destroy a key antiaircraft defensive complex containing surface-to-air missiles (SAM), an exceptionally heavy concentration of antiaircraft artillery, and other automatic weapons. The defensive network was situated to dominate the approach and provide protection to an important North Vietnam industrial center that was scheduled to be attacked by fighter bombers immediately after the strike by Maj. Dethlefsen's flight. In the initial attack on the defensive complex the lead aircraft was crippled, and Maj. Dethlefsen's aircraft was extensively damaged by the intense enemy fire. Realizing that the success of the impending fighter bomber attack on the center now depended on his ability to effectively suppress the defensive fire, Maj. Dethlefsen ignored the enemy's overwhelming firepower and the damage to his aircraft and pressed his attack. Despite a continuing hail of antiaircraft fire, deadly surface-to-air missiles, and counterattacks by MIG interceptors, Maj. Dethlefsen flew repeated close range strikes to silence the enemy defensive positions with bombs and cannon fire. His action in rendering ineffective the defensive SAM and antiaircraft artillery sites enabled the ensuing fighter bombers to strike successfully the important industrial target without loss or damage to their aircraft, thereby appreciably reducing the enemy's ability to provide essential war material. Maj. Dethlefsen's consummate skill and selfless dedication to this significant mission were in keeping with the highest traditions of the U.S. Air Force and reflect great credit upon himself and the Armed Forces of his country.