Thailand is the only Southeast Asian country never to have been taken over by a European power. A bloodless revolution in 1932 led to a constitutional monarchy. In alliance with Japan during World War II, Thailand became a US treaty ally following the conflict. A military coup in September 2006 ousted then Prime Minister THAKSIN Chinnawat. The interim government held elections in December 2007 that saw the former pro-THAKSIN People's Power Party (PPP) emerge at the head of a coalition government. The anti-THAKSIN People's Alliance for Democracy (PAD) in May 2008 began street demonstrations against the new government, eventually occupying the prime minister's office in August.