John R. Wilson joined the Army in 1942 and served in the Pacific Theater during World War II, reaching the rank of Major before being discharged in 1947. Shortly thereafter, he reenlisted as a Master Sergeant. When the Korean War began, MSG Wilson was assigned to the 25th Counterintelligence Corps (CIC) Detachment, 27th Infantry Regiment , 25th Infantry Division.

The invasion of South Korea by Communist North Korean forces on 26 June 1950 caught US leaders by surprise. The nation's intelligence assets had been focused almost entirely on the Soviet Union, and the intelligence troops that were on hand under General Douglas MacArthur's Far East Command were supporting an occupation force targeted against Japanese subversive elements rather than supporting a fighting force. US troops had no knowledge of the terrain, their maps were outdated, they lacked linguists, and the endless columns of South Korean refugees were infiltrated with North Korean soldiers and intelligence agents. It would take over a year before the language school in the US graduated its first 100 Korean linguists, leaving the critical job of human intelligence to interpreters of varying abilities and uncertain loyalties.

Despite these obstacles, the intelligence community rebuilt itself to support the combat forces who were ordered to fight on the Korean peninsula. One of these was MSG Wilson, an imposing figure at six feet, six inches tall. When alerted early in the morning of October 13, 1950 that enemy guerilla forces were moving to capture the small town of Pangso-ri, MSG Wilson quickly assembled his contingent of 30 Korean police and interpreters and organized them into teams surrounding the town. Taking with him four Koreans, Wilson personally led an attack on a house from which enemy soldiers had opened fire. Although Wilson himself was killed by sniper fire, his actions facilitated the capture of 21 of the enemy. For his gallantry under fire, Wilson was posthumously awarded the Silver Star.

A fellow member of MSG Wilson's team later wrote, "John earned many Silver Stars, which he never received, and was one of those who the Corps could truly say was a hero in his own right. John did much to enhance the position of the Counter Intelligence Corps within the military community who never really understood the function and purpose of intelligence agents being assigned to them." General John H. "Mike" Michaelis, commander of the 27th Infantry Regiment ("the Wolfhounds"), was convinced of his CIC Detachment's immediate value in combat. When the Army tried to move the CIC detachment to Division headquarters, Michaelis "raised all kinds of hell" and was quoted as saying, "How can I fight a damn war without counterintelligence people around me?"

In 1952, the CIC Center at Fort Holabird dedicated Wilson Hall in honor of MSG John Wilson's sacrifice. The US Army Intelligence Agency, which had moved to Fort Meade, Maryland in 1974, dedicated its command suite to Wilson's memory. MSG Wilson was inducted into the MI Hall of Fame in 1990, and in 1993, Wilson Barracks, part of the MI Noncommissioned Officers' Academy at Fort Huachuca, was dedicated to him as well.