How did the US end its role in Vietnam?

Answer 1

If a US Armored Cavalry Squadron (equivalent to a battalion) was in position for the night at an NDP site (Night Defensive Position), the US cavalrymen would be told the day/night previous, that "...an ARVN Cavalry Squadron was going to NDP with us tonight covering from that (pointing) position to that (again pointing) position; they'll have their own quartering parties...". Normally, the ARVN would ride in, it being near dark, ground guides and quartering parties would lead each armored vehicle to it's position for the night (circling the wagons). When completed, the ARVN's would become one half of the circle and the US the other half of the circle (the circle IS THE NDP SITE). At first dawn, the US Cavalry outfit would "crank up engines", and depart their former NDP site, which would be now occupied by ARVN Cavalry (or what ever mounted unit) which would then up the circle, left vacant by the departing US Cavalry. This was how a US "Ground" combat unit handed over the war to the South Vietnamese Army. The above description would be repeated all over the country.