Conclusion For 100 months, the USAF, the CIA, and the Thai government had assisted the Royal Lao government in staving off defeat at the hands of its enemies. If one measures the success of Barrel Roll by the priorities assigned to it by the U.S. government and military, it was a success. It had allowed the continuous prosecution of the Steel Tiger (and, post-1968, Operation Commando Hunt) interdiction campaigns against the Ho Chi Minh trail by keeping the neutralists in power. At the time of the cease-fire, communist forces controlled two-thirds of the land area and one-third of the population of Laos, approximately the same amounts that they had under their control in 1961. The imposition of a strategic stalemate had prevented the fall of the Vientiane government, which accomplished the secondary goal of the operation, protecting Thailand from communist attack (however unrealistic that threat appears today). This stalemate had been achieved with the loss of 131 U.S. aircraft between 1964 and 1973, a very low loss rate when compared to the operations discussed above. In his work Vietnam Air Losses, author Chris Hobson lists only 118 losses – 113 Air Force, four Navy, and one Marine Corps in Northern Laos. For the USAF, this success was achieved by conducting a shoestring operation, one that was fourth in priority for American air assets behind operations in South Vietnam, Operation Rolling Thunder, and Steel Tiger. After the close-out of aerial operations over North Vietnam, Barrel Roll still remained in last place. During its existence the campaign had utilized an average of only ten percent of the Air Force's tactical air effort in Southeast Asia. During the 1972 Nguyen Hue PAVN offensive, the number of airstrikes over northern Laos was reduced to only five percent of the total. There were problems - inflated bomb damage assessment reports during operations in northeastern Laos were common, but the cause was not difficult to discern. Mountainous terrain, poor weather, ground cover, the lack of ground forces for confirmation, and the language barrier all contributed to overestimation of the damage inflicted on communist forces by the bombing effort. The result was a skewed sense of the effectiveness and the capabilities of the campaign. The results of the campaign (which were made obvious by the repeating seasonal nature of PAVN and Pathet Lao offensives), however, indicated that American airpower was quite effective. The covert war in Laos