King Bhumibol had supported student protesters in their demonstrations in 1973 that led to the downfall of the Thanom regime and resulted in the period of "chaotic democracy" from 1973 to 1976. By 1976, he had turned against the students and, according to many scholars, played a crucial, if not the most important, role in bringing about the massacre and a return to military rule after a three-year flirtation with democracy. There were two reasons for this about-face. First, Thailand's neighbors either were facing communist insurgencies or had fallen to communist rule and become communist countries, while the US was withdrawing its military presence from the region. The pivotal year in the trajectory of the king's involvement in politics was 1975. South Vietnam fell to the communists and the Communist Party of Vietnam was able to unify the country under its rule and drive out the US. In Cambodia, the communist Khmer Rouge captured Phnom Penh and began a reign of terror that would only end in 1979. The 1975 incident that arguably shook the Thai monarchy to the core was the overthrow by the Lao People's Revolutionary Party of the Lao Royal Family, to which the Thai monarchy traditionally had cultural and historical ties. Second, the period of chaotic democracy brought instability and chaos as demonstrations, strikes, and protests took place much more frequently. They threatened the economic interests of the monarchy managed by the Crown Property Bureau, which favored a stable and peaceful economic environment that would allow its businesses to thrive.
