Central Office for South Vietnam

Central Office for South Vietnam (abbreviated COSVN /ˈkɑːzvɪn/; Vietnamese: Văn phòng Trung ương Cục miền Nam), officially known as the Central Executive Committee of the People's Revolutionary Party from 1962 until its dissolution in 1976, was the American term for the North Vietnamese political and military headquarters inside South Vietnam during the Vietnam War. It was envisaged as being in overall command of the communist effort in the southern half of the Republic of Vietnam (South Vietnam), which included the efforts of both People's Army of Vietnam (PAVN), the Viet Cong, and the People's Revolutionary Party. Some doubted its existence but in his memoirs the American commander in South Vietnam, General William Westmoreland, spoke of it as something whose existence and importance were not in doubt.^[2]

According to PAVN Major General and later dissident Trần Độ, COSVN did, in fact exist and was responsible for organising and directing the Viet Cong and served as overall command. It was however hierarchically directed by the Central Office (Trung ương Cục) which directed overall strategy, and was directly controlled by Hanoi. COSVN existed to operate the Viet Cong military and political effort.^[3]

MACV had imagined COSVN as a physically large, permanent structure due to their ability to carefully coordinate and direct Viet Cong activity entirely.^[4] It had become a near obsessive fixture for US and South Vietnamese leadership, given that it coordinated the complete activities of the Viet Cong.^[5] In fact these two organizations were composed of individuals living in thatched huts in the jungle just like all the guerrillas, and so there was no physical structure of any kind and existed as a highly-mobile headquarter to direct the Viet Cong war effort.^[3] The apparatus of the CO and COSVN had to move around all the time in order to avoid bombing and search and destroy operations conducted by the Americans, and was both physically capable of defending itself and highly mobile to continue to the nature of the war. Therefore, it can be stated that the CO and COSVN never had any kind of physical form.^[3]

US and South Vietnamese intelligence services had continually targeted COSVN for nearly a decade, given their near total importance in controlling the war effort.^[6] It had become an obsession of Richard Nixon in his view to win the war.^[7]

The Joint Chiefs of Staff claimed to have located the enemy's headquarters inside Cambodia — what the United States called the Central Office for South Vietnam, or COSVN. The chiefs envisioned it as a "Bamboo Pentagon," concealed beneath the jungle's canopy. They thought that if you could blow up this central headquarters, you could cripple the enemy's capacity to command and control attacks on US forces in South Vietnam. McCain said the United States should destroy it and win the damn war.

In 1965, nearly 400 US warplanes attempted to wipe out COSVN in an aerial attack, but had no effect on the elusive shadow command.^[3] Near-daily B-52 raids against its headquarters in Memot, Cambodia failed to kill any of its leadership and insertion of US / RVN Special Forces teams usually wound up dead or returning with heavy casualties, and it was described as "poking a beehive the size of a basketball".^[6][8] COSVN and CO continued to exist, evolving into the Provisional Revolutionary Government of the Republic of South Vietnam in 1969, and narrowly avoided capture of its entire headquarters by ARVN and Cambodian forces during the escape of the Provisional Revolutionary Government but still maintained its direct activities as serving as a Hanoi intermediary.