<Ul> <Li> Saigon </Li> <Li> US Embassy </Li> <Li> Tan Son Nhut Air Base </Li> <Li> Bien Hoa Air Base </Li> <Li> Hue </Li> <Li> Quảng Trị </Li> </Ul> <Li> Tan Son Nhut Air Base </Li> <Li> Bien Hoa Air Base </Li> <Li> Ban Houei Sane </Li>

What was the purpose of the invasion of cambodia