U.S. joint-service Operation Commando Hunt is launched. This operation was designed to interdict Communist routes of infiltration along the Ho Chi Minh Trail, through Laos into South Vietnam. The aerial campaign involved a series of intensive air operations by U.S. Air Force, Navy, and Marine Corps aircraft and lasted until April 1972. During the course of the operation, nearly 3 million tons of bombs fell on Laos. While Communist infiltration was slowed by this campaign, it was not seriously disrupted. Commando Hunt was ultimately considered a failure.