Now this is the definition of simplistic. Vietnamization actually worked, and like in Afghanistan, we got out but left enforcement and a policy and then we got Brandon and the same chaotic exit. After we left Vietnam, congress cut off most funding. Even my boss at the time voted to cut funds after he spent years resisting the most determined war opponents imaginable. The south Vietnamese literally had no bullets. It was congress who was responsible for the killing fields. Watergate obscured the slaughter.