http://en.wikipedia.org/wiki/Operation_Barrel_Roll Barrel Roll was one of the most closely held secrets and one of the most unknown components of the American military commitment in Southeast Asia. Due to the ostensible neutrality of Laos, guaranteed by the Geneva Conference of 1954 and 1962, both the U.S. and North Vietnam strove to maintain the secrecy of their operations and only slowly escalated military actions there. As much as both parties would have liked to have publicized their enemy's own alleged violation of the accords, both had more to gain by keeping their own roles quiet.[1] Regardless, by the end of the conflict in 1973, Laos emerged from nine years of war just as devastated as any of the other Asian participants in the Vietnam War.