they had the runs and were out of toilet paper
South Vietnam was overrun by communist forces.
Timely troop movements, troop support, supplies, and strategic air stikes.
"A" Troop was the only Troop from the 12th Cavalry sent to Vietnam.
LBJ
69,000
The United States began sending troops to Vietnam in a significant capacity in March 1965, when President Lyndon B. Johnson ordered the deployment of combat forces to support the South Vietnamese government against the communist Viet Cong. However, U.S. involvement in Vietnam had started earlier, with military advisors and support personnel being sent as early as the late 1950s. The troop presence escalated throughout the 1960s, peaking in 1969.
See website: Vietnam War
Slow and Honorable
WWII-Naval battles (Fleet actions); troop support; strategic strikes Vietnam War-Strategic strikes against North Vietnam & close air strikes for ground troops Today-Strikes against precision targets/strikes in support of ground troops
It depends on when in 1973 you're talking about. On March 23, 1973, as a result of the Paris Peace Accords, the US withdrew its remaining 2500 troops. The Department of Defense lists 1973 troop levels (presumably after the aforementioned troop withdrawal) at 50 US troops and 111000 South Vietnamese troops.
The peak US troop strength in Vietnam, of 543,482, was achieved on April 30, 1969.
One event that caused an escalation of troop involvement in Vietnam was the incident in 1964 at the Gulf of Tonkin.