In the early morning of December 8, 1941, the Japanese Southern Army invaded the coastal and eastern provinces of Thailand, initiating a hostility that lasted more than ten hours and resulted in more than a hundred and fifty casualties. Despite the invasion, the Thai government entered an alliance with the Japanese government and declared war on the United States and the United Kingdom on January 25, 1942. In previous historical scholarship, Thailand's entrance into the Second World War was seen as a result of pro-Japanese Thai politicians overpowering the pro-West faction in the government in order to align Thailand with the fascistic Greater East Asia Co-Prosperity Sphere. Nonetheless, such narrative failed to take into account the historical context and political agency among Thai political leaders. Therefore, to fully understand the causes and effects of Thailand's entrance into the Second World War, an investigation into the domestic political development in Thailand must be considered. This thesis argues that rather than the geopolitical affiliation among Thai leaders, it was the breakdown in the relationship between two dominant factions in the Thai government—the civilian politicians and the military officers—that caused Thailand's entrance into the Second World War as a Japanese ally. From 1927, a new class of professional elite—composed of young military officers and civilian elites—began to foment a political opposition to the Thai monarchy and its royalist supporters, establishing the political party called Khana Ratsadorm. Then, in 1932, Khana Ratsadorn conducted a coup d'etat against the monarchy and installed themselves to oversee the Thai government, effectively replacing the monarchy as the hegemonic power in the Thai state. However, when Japan invaded on December 8, 1941, the shared goal between the military-civilian coalition diverged as the military faction sought to appease Japan to prevent a possible disarmament of the Thai armed forces while the civilian faction preferred to limit Japanese interferences. After the invasion, the military faction saw the civilian faction as impediment to their survival. This led military leaders to 1) purge prominent civilian politicians from the cabinet on December 16, 2) sign an alliance pact with Japan on December 21, 1941, and 3) declared war on Great Britain and the United States on January 25, 1942. This breakdown in the hegemonic coalition pushed the civilian faction to ally with the resurgent royalists, forming a resistance movement that toppled the military faction-dominated government. Nevertheless, the civilian-royalist coalition did not last, and the factional antagonism between the military officers, civilian politicians, and the royal house supporters has dominated Thai politics ever since. Thus, Thailand's alliance with Japan and declaration of war against Britain and the United States came as a result of the breakdown between military and civilian coalition in the Thai cabinet, creating a pattern of political factionalism in Thai domestic politics until today.
"},{"label":"Degree","value":["Bachelor of Arts with Departmental Honors"]},{"label":"Author-supplied Keywords","value":["The Second World War","Thai political history","Civil-military relation"]},{"label":"Administrative Note","value":"Drupal Node ID: 23926