US. NAVY SEABEEs during the Vietnam War:
The Navy's Construction Battalions were conceived to replace civilian construction companies then on contract to the Navy soon after the U.S. was attacked at Pearl Harbor. There was roughly 70,000 civilian contractors working on various 'U.S.' bases stationed overseas. But International law made it illegal for civilian workers to resist an attack. For them do so, would classify them as guerrillas (war participants) and legally could lead to summary execution. So that had to be changed. Ding... the need for Navy Construction Battalion's.