President Kennedy approves sending 400 Special Forces troops and 100 other U.S. military advisers to South Vietnam. On the same day, he orders the start of clandestine warfare against North Vietnam to be conducted by South Vietnamese agents under the direction and training of the CIA and U.S. Special Forces troops. Kennedy’s orders also called for South Vietnamese forces to infiltrate Laos to locate and disrupt communist bases and supply lines there.

READ MORE: How the Vietnam War Ratcheted Up Under 5 U.S. Presidents