The term fragging is used to describe the deliberate killing or attempted killing by a soldier of a fellow soldier, usually a superior officer or non-commissioned officer (NCO). The word was coined by U.S. military personnel during the Vietnam War, when such killings were most often attempted with a fragmentation grenade, sometimes making it appear as though the killing was accidental or during combat with the enemy. The term fragging is now often used to encompass any means used to deliberately and directly cause the death of military colleagues.
The high number of fragging incidents in the latter years of the Vietnam War was symptomatic of the unpopularity of the war with the American public and the breakdown of discipline in the U.S. Armed Forces. Documented and suspected fragging incidents totaled nearly nine hundred from 1969 to 1972. Fragging has not been as frequent since the Vietnam War ended.
Soldiers have killed colleagues, especially superior officers, since the beginning of armed conflict with many documented instances throughout history. However, the practice of fragging seems to have been relatively uncommon in American armies until the Vietnam War. The prevalence of fragging was partially based on the ready availability of fragmentation hand grenades. Grenades were untraceable to an owner and did not leave any ballistic evidence. M18 Claymore mines and other explosives were also occasionally used in fragging, as were firearms, although the term, as defined by the military during the Vietnam War, applied only to the use of explosives to kill fellow soldiers. Most fragging incidents were in the Army and Marine Corps. Fragging was rare among Navy and Air Force personnel who had less access to grenades and weapons than did soldiers and marines.
The first known incidents of fragging in South Vietnam took place in 1966, but events in 1968 appear to have catalyzed an increase in fragging. After the Tet Offensive in January and February 1968, the Vietnam War became increasingly unpopular in the United States and among American soldiers in Vietnam, many of them conscripts. Secondly, racial tensions between white and African-American soldiers and marines increased after the assassination of Martin Luther King in April 1968. With soldiers reluctant to risk their lives in what was perceived as a lost war, fragging was seen by some enlisted men "as the most effective way to discourage their superiors from showing enthusiasm for combat."