During World War II, Vessey served with the 34th Infantry Division. The experience of early American setbacks in North Africa left Vessey with a lifelong appreciation of the need for realistic combat training, modern equipment, physical fitness, and air-ground cooperation. When Major General Omar Bradley, Commander of II Corps in North Africa, launched the U.S. drive on Bizerte in April 1943, he gave the 34th the most difficult objective: the well-defended Hill 609. In the first clear-cut U.S. Army victory of the campaign, the 34th Division took its objective, opening the way for the U.S. advance on Bizerte. Vessey, who had been a First Sergeant since 1 September 1942, later described being a first sergeant in combat as the “toughest job” he had. He was with the 34th when it entered the Anzio beachhead in Italy in May 1944; there he received a battlefield commission as a second lieutenant, serving as a forward observer.
After the war, most of Vessey’s service continued to be in field artillery assignments. In the 1950s he served with the 4th Infantry Division in Germany and the Eighth U.S. Army in the Republic of Korea. During this period he also attended the Command and General Staff College at Fort Leavenworth, Kansas.
By the time Vessey became a lieutenant colonel, he had earned enough credits through night school and correspondence courses for a Bachelor of Science degree, which he received from the University of Maryland University College in 1963. In 1965, he received a master of science from George Washington University. From 1963 to 1965 Vessey commanded the 2d Battalion, 73rd Field Artillery in the 3rd Armored Division; then he spent a year as a student at the Industrial College of the Armed Forces.
During the Vietnam War, Vessey served for a year as Executive Officer of the 25th Infantry Division Artillery in Vietnam. In March 1967, when acting as Commander of the 2nd Battalion, 77th Artillery, he was given the mission of establishing a fire support base at Suoi Tre during Operation Junction City. Located deep in enemy-controlled territory, Vessey and his men oriented the firebase’s defenses on the enemy’s likely avenues of approach and rehearsed counterattack plans. During the attack by a reinforced regiment, the base was partially overrun. Vessey and his men fired their howitzers directly into the enemy ranks. Although greatly outnumbered, the defenders, aided by gunships and artillery, killed four hundred of their assailants while successfully defending the firebase. Lieutenant Colonel Vessey received the Distinguished Service Cross for his actions during the battle.
From Vietnam, he went to Germany, to serve first as Commander of the 3d Armored Division Artillery from October 1967 until March 1969 and then as Division Chief of Staff for a year. He was promoted to colonel in November 1967. Vessey went back to Southeast Asia in December 1970 to head the U.S. Army Support Command, Thailand. In January 1972 he went into Laos to coordinate all US military operations in support of the war in Laos. Vessey worked with the U.S. ambassador, the CIA station chief, and an assortment of military contingents. When the Laotian ceasefire came in February 1973, the Royal Lao government controlled all major cities and the vast majority of the population.
Upon his return to the United States, Vessey became Director of Operations in the Office of the Deputy Chief of Staff for Operations and Plans. Promoted to major general in August 1974, he assumed command of the 4th Infantry Division (Mechanized) at Fort Carson, Colorado. Promoted to lieutenant general in September 1975, he became the Army’s Deputy Chief of Staff for Operations and Plans.
Vessey received his fourth star in November 1976. From 1976 to 1979 he served in the Republic of Korea as Commanding General of the Eighth U.S. Army; Commander of U.S. Forces, Korea; and Commander in Chief of the United Nations Command. In 1978, he became the first Commander in Chief of the Republic of Korea-United States Combined Forces Command. His tour was marked by increased tension caused by evidence of a North Korean buildup and by President Jimmy Carter’s 1977 announcement that U.S. ground forces would be withdrawn. Vessey worked to assuage South Korean concerns and change the President’s decision. After Carter’s 1979 visit, withdrawal plans were suspended and then cancelled. From July 1979 until June 1982, General Vessey served as Vice Chief of Staff of the Army.
On June 18, 1982, he became the tenth Chairman of the Joint Chiefs of Staff and the last World War II combat veteran to serve in the position. General Vessey was the only Chairman who had been neither a Service Chief nor a commander of a unified or specified command. He served as Chairman during a period of unprecedented growth in peacetime defense spending and an expanded U.S. military presence worldwide intended to counter growing Soviet military power.
Vessey and the Service Chiefs believed that their overriding task lay in convincing Soviet leaders that their quest for military superiority and geostrategic advantage was fruitless. In Europe, they pushed the controversial but successful deployment of Pershing II and ground-launched cruise missiles to offset the Soviet SS-20 missiles. In Southwest Asia, highly visible US military activities underscored the US commitment to defend its vital interests in the region. In Central America, training and intelligence were provided to support counter-insurgency efforts.
Believing that it was a mistake to commit a superpower’s forces to a peacekeeping mission, Vessey and the Joint Chiefs in 1982 and 1983 advised against deployment of a Marine contingent to Lebanon as part of a multinational peacekeeping force intended to restore peace among warring factions there. Their advice was not taken, and on 23 October 1983 a truck-bomb attack on the Marine headquarters building in Beirut killed 241 US Marines and Army soldiers. In late February 1984 President Reagan withdrew the contingent from Lebanon.
Vessey stressed the need for improvement of war plans and, for the first time, JCS members along with commanders of unified and specified commands personally participated in war games. Realizing the need to strengthen the joint system, Vessey and the Service Chiefs improved Joint Staff operations by adding a capability for budgetary analysis and by improving the quality of its personnel, changes that did not require legislation.
Secretary of Defense Caspar Weinberger understood the importance of decentralization; he authorized Vessey to direct military operations on the Secretary’s behalf. The 1983 Grenada operation, for example, was planned by Atlantic Command, reviewed by the JCS, and approved by Secretary Weinberger and the President—all in four days. Vessey oversaw execution of the operation that rescued US citizens and brought a pro-US government into power.
During Vessey’s tenure there was increased emphasis on space as a theater of operations. In early 1983, the Joint Chiefs mentioned to the President that defense against nuclear-armed missiles might be technically feasible in the next century. To their surprise, Reagan seized upon the concept and on 23 March 1983 announced his vision of the Strategic Defense Initiative (SDI). Realizing the enormous military advantages to be gained from operations in space and to support SDI, the JCS recommended the establishment of a unified command for space. US Space Command was activated on 23 September 1985.