February 14, 1962 – In early 1962, U.S. involvement in Vietnam was still limited to a few hundred military advisors under direction on the U.S. Military Assistance Command, Vietnam (MACV). On February 14, at a press conference, President Kennedy authorized military advisors to return fire if fired upon- – essentially acknowledging for the first time that the U.S. personnel were actively involved in combat.
“The training missions we have [in South Vietnam] have been instructed that if they are fired upon, they are of course to fire back, but we have not sent combat troops in [the] generally understood sense of the word.”
Within a year, there would be more than 15,000 U.S. troops in Vietnam. The escalation in troop levels would continue another 5 years, finally maxing out at over 500,000 in 1968.