International Community

Sadly, there was lack of help from the International Community. Once the Khmer Rouge took over, they expelled all foreigners from the country and made it hard for anyone to come in and help. They also made it nearly impossible for outside countries to recieve firsthand knowledge about what was going on within the walls of Cambodia. The International Community did not have any impact on the genocide in Cambodia. 

United States Involvement 

The United States' policy actually supported the rise of the Pol Pot and the Khmer Rouge. The reason we supported them, was because they were supporting us in the war in Vietnam. The United States did not take any significant steps to help the victims in Cambodia. They were more focused one communism and winning the Cold War. The only impact that the United States had on the Cambodian genocide was a bad impact. 

Other Involvement

1978-Vietnam invades Cambodia to stop Khmer Rouge border attacks.

Honestly, no countries (other than small organizations) made any compelling effort to physically help the innocent victims of the genocide in Cambodia.