Timeline of United States military operations communist attack on a U.S. installation in central Vietnam, the United States escalated its participation in the war to a peak of 543,000 military personnel by April 1969. 1961: Cuba: The Bay of Pigs Invasion, known in Hispanic America as Invasión de Bahía de Cochinos (or Invasión de Playa Girón or Batalla de Girón), was an unsuccessful military invasion of Cuba undertaken by the CIA-sponsored paramilitary group Brigade 2506 on April 17, 1961. 1962: Thailand: The Third Marine Expeditionary Unit landed on May 17, 1962 to support that country during the threat of Communist pressure from outside; by July 30,
CIA activities in Vietnam in the mountains of Laos, Thailand, and Vietnam, and the CIA quickly realized the potential use of the Hmong as guerrilla fighters against Laotian as well as North Vietnamese communist forces. First donations of food, blankets, and then by January 24, 1961 300 Hmong received weapons to Vang Pao's troops, the CIA sent men to train Hmong fighters in guerrilla tactics, eventually engaging soon-to-be-General Pao's approximately 10,000 men. These Hmong forces would prove valuable to the CIA's tactics for the remainder of the war, despite insecurities on both sides as to the allegiance of the other. It was during 1961