John Learie Estrada (born September 27, 1955) is the former United States Ambassador to Trinidad and Tobago and a former United States Marine who served as the 15th Sergeant Major of the Marine Corps from 2003 to 2007. Estrada stepped down from that post on April 25, 2007, turning over the billet to the next sergeant major, Carlton Kent. Estrada then retired from the military in June 2007, after over 33 years of service. He has also worked as a senior manager for Lockheed Martin Training Solutions from 2008 onward. Estrada was nominated to be the United States Ambassador to Trinidad and Tobago in July 2013, was approved for the position on February 12, 2016, and became the ambassador on March 17. Early life and education Estrada was born in Laventille, Trinidad and Tobago on September 27, 1955. He immigrated to the United States as a teenager and became a naturalized citizen in 1988. Military career Estrada enlisted in the United States Marine Corps on September 19, 1973, and attended recruit training at Marine Corps Recruit Depot Parris Island in South Carolina. After completing F-4 aircraft maintenance schools at Naval Air Station Memphis, and Marine Corps Air Station Cherry Point, North Carolina, Private First Class Estrada was assigned to VMFA-451 at Marine Corps Air Station Beaufort, South Carolina in March 1974. In December 1974, Lance Corporal Estrada was transferred to VMFA-232, 1st Marine Aircraft Wing, Marine Corps Air Station Iwakuni, Japan. He was meritoriously promoted to corporal in March 1975. In February 1976, Sergeant Estrada served with VMFAT-101, Marine Corps Air Station Yuma, Arizona. In September 1977, he transferred to VMFA-314, Marine Corps Air Station El Toro, CA. Reassigned to VMFA-323 in December 1978, he deployed with the squadron in November 1979 for 7 months aboard the aircraft carrier USS Coral Sea to the Western Pacific and Persian Gulf. In June 1980, Staff Sergeant Estrada transferred to VMFA-321, Marine Aircraft Group 41, Detachment "A" at Andrews Air Force Base, Maryland. In August 1982, Staff Sergeant Estrada was ordered to drill instructor duty at Marine Corps Recruit Depot San Diego, where he served with Kilo Company, 3rd Recruit Training Battalion. He was meritoriously promoted to gunnery sergeant in January 1984. In October, Estrada returned to Beaufort for duty with VMFA-251 as the non-commissioned officer in charge of the Airframes Division. In November 1985, he was reassigned to VMFA-451 and deployed to