タイ・フランス領インドシナ紛争
Phibun and the Thai public viewed the outcome of the Franco-Thai War as a victory, but it resulted in the rapidly expanding Japanese gaining the right to occupy French Indochina. Although Phibun was ardently pro-Japanese, he now shared a border with them and felt threatened with a potential Japanese invasion. Phibun's administration also realised that Thailand would have to fend for itself if a Japanese invasion came, considering its deteriorating relationships with Western powers in the area.