17th April, 1975 marked the fall of Phnom Penh.
A “butterfly effect” of the Vietnam war.
The Government of Phnom Penh was forced to surrender.
The Khmer Rouge captured the already fallen capital, the Khmer Republic that came in power along side a bloodless coup by Lt. Gen. Lon Nol, who fled the country when the country fall, enjoying life in the coast of Hawaii. Coward or not, I am not the person to say.