During the Cold War, Thailand’s regional role can be clearly understood in relations with the U.S.’ anti-communist policy in Southeast Asia. Thailand’s significance in regional security was reflected in the view of its security patron, the U.S. The latter viewed that Thailand was the heart of the region and its freedom would be critical to the survival of Southeast Asia. The U.S., there-fore, decided to position its defensive system (Stanton, 1954), leading to the establishment of the headquarters of the South East Asian Treaty Organization (SEATO) in Bangkok in 1955. As a critical fortress of the free world in the region, the U.S. poured military and economic assistance to Thailand during the Cold War. Thailand’s role was then important in deterring the expansion of Vietnamese influence in mainland Southeast Asia. Thailand accommodated both U.S.’ covert and overt military operations in the region in Laos and during the Vietnam War