Tonkin to Saigon: a Cold War proxy that remade Indochina
From about 1955 to 30 April 1975, North Vietnam and its allies fought South Vietnam, the United States, and partners across Vietnam, Laos, and Cambodia. Geneva's 1954 split at the seventeenth parallel internationalised a struggle that French defeat had not ended.
After the First Indochina War, the Viet Minh under Ho Chi Minh took the north while Ngo Dinh Diem's State of Vietnam held the south with American backing. The 1964 Gulf of Tonkin incident produced a congressional resolution letting Lyndon Johnson bomb the north and pour in combat troops without a formal declaration of war. The 1968 Tet Offensive was a communist tactical reverse that nonetheless eroded U.S. domestic support for the commitment.
Richard Nixon's Vietnamization from 1969 enlarged the ARVN as American ground forces shrank; by 1972 most U.S. troops were gone, though Linebacker air power still blunted Hanoi's Easter Offensive. Vietnamese military and civilian deaths are estimated between about 970,000 and three million. Cambodia lost on the order of 275,000 to 310,000 lives, Laos some 20,000 to 62,000, and 58,220 American service members died. Postwar repression and economics helped drive the boat-people exodus; roughly a quarter million of the millions fleeing Indochina perished at sea.
English usually says Vietnam War or Second Indochina War; other labels track politics on each side. The conflict's mix of nationalism, communism, and superpower aid turned a local partition into a regional catastrophe whose refugee waves outlasted the fall of Saigon on 30 April 1975.
Escalation built up step by step. Hanoi supplied and later directed the Viet Cong insurgency, which intensified its guerrilla campaign from 1957; a 1958 incursion into Laos opened the Ho Chi Minh trail, and regular northern soldiers were being slipped south by 1961. Diem himself died in 1963 when his own generals, with Washington's blessing, overthrew him. American strength then climbed from 184,000 personnel in 1966 to 536,000 by 1969, and toxic herbicides were sprayed over a fifth of the southern jungle, leaving lasting health damage.
Source: Vietnam War
