Vietnam War: Operation Jefferson Glenn begins: The United States 101st Airborne Division and the South Vietnamese 1st Infantry Division initiate a new operation in Thừa Thiên-Huế Province.
The 101st Airborne Division (Air Assault) ("Screaming Eagles") is a light infantry division of the United States Army that specializes in air assault operations. It can plan, coordinate, and execute multiple battalion-size air assault operations to seize terrain. These operations can be conducted by mobile teams covering large distances, fighting behind enemy lines, and working in austere environments with limited or degraded infrastructure. Its unique battlefield mobility and high level of training have kept it in the vanguard of U.S. land combat forces in recent conflicts: for example, foreign internal defense and counterterrorism operations in Iraq, in Afghanistan, and in Syria, as part of Operation Inherent Resolve.
Established in 1918, the 101st Division was first constituted as an airborne unit in 1942. During World War II, it gained renown for its role in Operation Overlord (the D-Day landings and airborne landings on 6 June 1944, in Normandy, France); Operation Market Garden; the liberation of the Netherlands; and its action during the Battle of the Bulge around the city of Bastogne, Belgium. During the Vietnam War, the 101st Airborne Division fought in several major campaigns and battles, including the Battle of Hamburger Hill in May 1969. In mid-1968, the division was reorganized and redesignated as an airmobile division; in 1974, as an air assault division. The titles reflect the division's shift from airplanes to helicopters as the primary method of delivering troops into combat.
At the height of the War on Terror, the 101st Airborne Division (Air Assault) had over 200 aircraft. This shrank to just over 100 aircraft with the inactivation of the 159th Combat Aviation Brigade in 2015, making it no different in configuration from the Army's other light infantry divisions. In 2019, media reports suggested the Army was working to restore the 101st's aviation capabilities so it can return to lifting an entire brigade in one air assault operation.Division headquarters is at Fort Campbell, Kentucky. Many current members of the 101st are graduates of the U.S. Army Air Assault School, which is co-located with the division. The school is known as one of the Army's most difficult courses; only about half of those who begin it graduate.The Screaming Eagles have been referred to as "the tip of the spear" by U.S. Secretary of Defense, Robert Gates, and the most potent and tactically mobile of the U.S. Army's divisions by General Edward C. Meyer, then Chief of Staff of the Army.
The Vietnam War (Vietnamese: Chiến tranh Việt Nam), also known as the Second Indochina War, was a conflict in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. It was the second of the Indochina Wars and was officially fought between North Vietnam and South Vietnam. North Vietnam was supported by the Soviet Union, China, and other communist allies; South Vietnam was supported by the United States and other anti-communist allies. The war is widely considered to be a Cold War-era proxy war. It lasted almost 20 years, with direct U.S. involvement ending in 1973. The conflict also spilled over into neighboring states, exacerbating the Laotian Civil War and the Cambodian Civil War, which ended with all three countries becoming communist states by 1975.
The conflict emerged from the First Indochina War between the French colonial government and a left-wing revolutionary movement, the Viet Minh. After the French military withdrawal from Indochina in 1954, the U.S. assumed financial and military support for the South Vietnamese state. The Việt Cộng (VC), a South Vietnamese common front under the direction of North Vietnam, initiated a guerrilla war in the south. North Vietnam had also invaded Laos in 1958 in support of insurgents, establishing the Ho Chi Minh Trail to supply and reinforce the Việt Cộng.: 16 By 1963, the North Vietnamese had sent 40,000 soldiers to fight in the south.: 16 U.S. involvement escalated under President John F. Kennedy through the MAAG program, from just under a thousand military advisors in 1959 to 23,000 in 1964.: 131 In the Gulf of Tonkin incident in August 1964, a U.S. destroyer clashed with North Vietnamese fast attack craft. In response, the U.S. Congress passed the Gulf of Tonkin Resolution and gave President Lyndon B. Johnson broad authority to increase U.S. military presence in Vietnam. Johnson ordered the deployment of combat units for the first time and increased troop levels to 184,000. The People's Army of Vietnam (PAVN) (also known as the North Vietnamese Army or NVA) engaged in more conventional warfare with U.S. and South Vietnamese forces (Army of the Republic of Vietnam (ARVN)). Despite little progress, the U.S. continued a significant build-up of forces. U.S. and South Vietnam forces relied on air superiority and overwhelming firepower to conduct search and destroy operations, involving ground forces, artillery, and airstrikes. The U.S. also conducted a large-scale strategic bombing campaign against North Vietnam.: 371–4 The communist Tet Offensive throughout 1968 caused U.S. domestic support for the war to fade. The VC sustained heavy losses during the Offensive and subsequent U.S.-ARVN operations.: 481 The CIA's Phoenix Program further degraded the VC's membership and capabilities. By the end of the year, the VC insurgents held almost no territory in South Vietnam, and their recruitment dropped by over 80%, signifying a drastic reduction in guerrilla operations, necessitating increased use of PAVN regular soldiers from the north. In 1969, North Vietnam declared a Provisional Revolutionary Government (the PRG) in the south to give the reduced VC a more international stature, but from then on, they were sidelined as PAVN forces began more conventional combined arms warfare. By 1970, over 70% of communist troops in the south were northerners, and southern-dominated VC units no longer existed. Operations crossed national borders: North Vietnam used Laos as a supply route early on, while Cambodia was also used starting in 1967; the U.S. bombed the Laotian route starting in 1964, and the Cambodian route in 1969. The deposing of the monarch Norodom Sihanouk by the Cambodian National Assembly resulted in a PAVN invasion of the country at the request of the Khmer Rouge, escalating the Cambodian Civil War and resulting in a U.S.-ARVN counter-invasion.
In 1969, following the election of U.S. President Richard Nixon, a policy of "Vietnamization" began, which saw the conflict fought by an expanded ARVN, with U.S. forces sidelined and increasingly demoralized by domestic opposition and reduced recruitment. U.S. ground forces had largely withdrawn by early 1972 and support was limited to air support, artillery support, advisers, and materiel shipments. The ARVN, with U.S. support, stopped the first and largest mechanized PAVN offensive during the Easter Offensive of 1972. The offensive failed to subdue South Vietnam, but the ARVN itself failed to recapture all lost territory, leaving its military situation difficult. The Paris Peace Accords of January 1973 saw all U.S. forces withdrawn; the Case–Church Amendment, passed by the U.S. Congress on 15 August 1973, officially ended direct U.S. military involvement.: 457 The Peace Accords were broken almost immediately, and fighting continued for two more years. Phnom Penh fell to the Khmer Rouge on 17 April 1975, while the 1975 Spring Offensive saw the Fall of Saigon by the PAVN on 30 April; this marked the end of the war, and North and South Vietnam were reunified the following year.
By 1970, the ARVN was the world's fourth largest army, and the PAVN was not far behind with approximately one million regular soldiers.: 770 The war exacted an enormous human cost: estimates of the number of Vietnamese soldiers and civilians killed range from 966,000 to 3 million. Some 275,000–310,000 Cambodians, 20,000–62,000 Laotians, and 58,220 U.S. service members also died in the conflict, and a further 1,626 remain missing in action.The Sino-Soviet split re-emerged following the lull during the Vietnam War. Conflict between North Vietnam and its Cambodian allies in the Royal Government of the National Union of Kampuchea, and the newly formed Democratic Kampuchea began almost immediately in a series of border raids by the Khmer Rouge, eventually escalating into the Cambodian–Vietnamese War. Chinese forces directly invaded Vietnam in the Sino-Vietnamese War, with subsequent border conflicts lasting until 1991. The unified Vietnam fought insurgencies in all three countries. The end of the war and resumption of the Third Indochina War would precipitate the Vietnamese boat people and the larger Indochina refugee crisis, which saw millions of refugees leave Indochina (mainly southern Vietnam), an estimated 250,000 of whom perished at sea. Within the U.S., the war gave rise to what was referred to as Vietnam Syndrome, a public aversion to American overseas military involvements, which together with the Watergate scandal contributed to the crisis of confidence that affected America throughout the 1970s.