What were the Prevention Acts of the Vietnam War?
Not entirely sure what your talking about. There was an agreement signed by France and the North Vietnamese in 1954 called the "Geneva Accords" which made a tentative peace between France and the People's Army. It split the socialist north from the free south, but called for national elections in 1956 which never actually occurred. I don't think there were many other preventative measures taken, since when the US entered following the Gulf of Tonkin incident most Americans were in favor of additional US involvement in Vietnam.