By 1970, Cambodia’s neutrality would be proven false when the US supported a coup to put a pro-American, anti-Vietnamese government in power. American involvement caused the North Vietnamese to act and they began moving their military installations to the northeastern part of the country to protect them from US bombers, essentially taking over that part of Cambodia. Whilst there, they would lend their support to a then little known guerrilla group, the Khmer Rouge. In response to the military build up in the northeast, the Kingdom of Cambodia would in turn increase their military presence in order to counteract the North Vietnamese and Khmer Rouge.
The US would increase their support for their allies in Cambodia and South Vietnam with financial support and an aerial bombing campaign. In response to this, the Soviet Union would increase their support for the North Vietnamese helping them to invade Cambodia. The resulting war forced Prince Sihanouk to seek the help of the Khmer Rouge in order to resolve the conflict but that would soon backfire as the Cambodian coup of 1970 would oust him from power causing him to flee the country.
The United States desperately tried to return the government they had backed to power but by April 1975 they had resigned themselves to defeat and pulled out of the country entirely, leaving the Khmer Rouge under the control of Pol Pot, to completely take over the country. This move by the US would usher in an age of genocide that would far outweigh the 300,000 people who had already lost their lives due to the civil war. Pol Pot’s regime would eventually oversee the deaths of over 2 million people.
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