The Case–Church Amendment had effectively nullified the Paris Peace Accords, and as a result the United States had cut aid to South Vietnam drastically in 1974, just months before the final enemy offensive, allowing North Vietnam to invade South Vietnam without fear of U.S. military action. As a result, only a little fuel and ammunition were being sent to South Vietnam. South Vietnamese air and ground vehicles were immobilized by lack of spare parts. Troops went into battle without batteries for their radios, and their medics lacked basic supplies. South Vietnamese rifles and artillery pieces were rationed to three rounds of ammunition per day in the last months of the war. Without enough supplies and ammunition, ARVN forces were quickly thrown into chaos and defeated by the well-supplied PAVN, no longer having to worry about U.S. bombing.