THE VIETNAM CONFLICT FROM 1945 TO 1975

The Vietnam War was not only the longest armed conflict in the 20^th century, but also the first military defeat of the United States in history. Besides Vietnam as a venue of the Cold War has changed the attitude of many people (both Americans and people from outside USA) towards the superpower. The image of America setting an example to other countries began to fade.

Index

A photo of the self-immolation of Buddhist monk Thich Quang Duc in the streets of

Saigon

French colonialism in Vietnam through 1945

Vietnam during French colonial power and Japanese occupation

The revolution of 1945

The United States and the French Indochina War, 1946-1954

French efforts to regain control over Vietnam

America's foreign politics

The First Vietnam War / Dien Bien Phu

Nation Building in South Vietnam, 1954-1960

The Geneva Accords

The United States and South Vietnam

Opposition to the Diem regime

Communism in North Vietnam

Insurgency and counterinsurgency, 1961-1964

Armed conflicts between the NLF and the ARVN

The overthrow of Ngo Dinh Diem

Hanoi's measures in response

Johnson's decisions for war, 1964-1965

The Gulf of Tonkin events

Rolling Thunder and the deployment of American combat forces

The beginnings of the American Vietnam War, 1965-1967

Air war

Ground war

The political situation in South Vietnam

The Tet Offensive: a turning point (1968)

Khe Sanh / Tet

Public opinion in America

Nixon and Vietnamization, 1969-1971

Vietnamization policy

The invasion of Cambodia

Peace negotiations

The end of the American commitment / Vietnam in the aftermath of the war, 1972-1975

The Easter Offensive

The peace settlement

Post-war Vietnam

Map of Vietnam

Pattern of the Tet Attacks

(~6000 words)

Main Source: George C. Herring, America's Longest War. The United States and Vietnam, 1950-1975 (3^rd ed.)

© 03/2002 by Martin Beletz

French colonialism in Vietnam through 1945

Until 1887 France had subdued the countries of Vietnam, Cambodia and Laos and began to expand its colonial power there by establishing the Indochinese Union. When in 1897 all Vietnamese resistance was broken, the French started to centralize the administration, to restrict the autonomy of the villages and to introduce forced labour. Receipts from forced expropriations were used for extending the infrastructure. It was only a small (urban) part of the population who was able to benefit from increasing colonial trade and the establishing of a French determined education. Consequently a small elitist intellectual class developed, among who opposition to French colonization grew. There was also a development of communist tendencies influenced by international circumstances (the revolution in Russia in 1917, the rebellions in China in 1911 and the promise of equalization of all men which communism had conveyed), whereas the world economic crisis doubted capitalism. In the end of the thirties the French power increasingly oppressed people of a different view (anti-colonialists, nationalists, communists). In 1939 2,000 dissidents were arrested. In November of 1940 a revolt of the Communist Party was put down brutally and resulted in about 5,000 arrests and a hundred executions.

Hitler's victory over France in June of 1940 and the Japanese occupation of Southeast Asia shortly after the incident at Pearl Harbor gave an impetus to Vietnamese liberation movements. The French administration backed up by 27,000 soldiers stationed in Vietnam now collaborated with the Japanese in ruling a country of 18 millions inhabitants. In 1941 the resistance formed up within the "Vietminh" (abbr. for "League for the Independence of Vietnam"). The Vietminh, mainly consisting of communist intellectuals, aimed to spread a sense of Vietnamese nationalism within the population. Since the rural population amounted to 95 per cent of the people, they sent intellectuals into the villages serving as commanders, teachers or propagandists. Their success in integrating hundred thousands of people during the post-war years also refers to a large part to a heavy famine (it claimed over a millions deaths), which was caused by inflation and the general exploitation of the country by its belligerent ruling powers. Because of his organizational talent and his indomitable will Ho Chi Minh soon became the undisputed leader of the communist Vietminh. The son of a mandarin at the imperial court in Hue had departed Vietnam in 1912 as a cabin boy and had settled in France, where he had joined the Communist party. In 1930 he had organized the Indochinese Communist party and he should also be the central figure in the revolution. When the Japanese deposed the French puppet government in March of 1945, the Vietminh officially collaborated with the Allies and got support from a unit of the U.S. secret service OSS (Office of Strategic Services), until the surrender of Japan five months later. On September 2 Ho Chi Minh, who even had worked as an OSS agent, proclaimed the independence of his country and ironically U.S. officers and aircraft attended the independence celebrations in Hanoi.

The United States and the French Indochina War, 1946-1954

According to the Potsdam Conference, British forces, followed by French ones, occupied the southern part of Vietnam, whereas the north was occupied Chinese. In March of 1946 the Vietminh negotiated a compromise with the French by accepting French comtrol for five years in North Vietnam, too, where the sphere of Vietnam influence was greatest. In return the French recognized Vietnam as a free state within the French Union, but subsequently France didn't keep to the agreement. It separated the South (Cochinchina) from Annam and Tonkin in order to maintain absolute control over the region of their greatest economic interest. In November of 1946, a French cruiser shelled Haiphong, a port city in the northern part of Vietnam (Tonkin) for flimsy reasons, claiming the death of 6,000 civilians. This incident meant the beginning of a war which would last (in its various phases) almost thirty years.

The American Indochina policy took a turn after the Second World War. In the 1930s, a competition developed between the United States and Japan concerning the domination of the Southeast Asian market. French monopolies restricted America's economical connections to Indochina. For this reason the French effort to regain control of Vietnam met with opposition of the U.S. under Roosevelt's presidency. Besides Roosevelt spoke against any form of colonialism and attempted to convince the colonial powers to gradually dismiss their possessions in Asia into independence. But for France, Vietnam was of economical importance for its recovery after World War II. When the Japanese moved forward to Indochina in 1941, the French colonies suddenly became strategically important for America. After the Soviet Union had subjugated Eastern Europe, the government of Roosevelt's successor Harry S. Truman endeavoured to contain its expansion and thus the dissemination of communism. For that purpose America had an interest in promoting West European powers in order to establish a balance there. When in 1947 the Vietminh tried to convince their former ally to politically and economically support them in the war against the French offering it economical benefits, the U.S. refused. From the point of view of America, it was no longer a colonial war against a nationalist liberation movement but a struggle against Moscow-directed communism in the periphery. Although there was no evidence of Soviet contact with the Vietminh, Ho Chi Minh was virtually considered as Stalin's representative in Indochina. The "loss" of China for the Communists led by Mao Zetung and the ignition of the first Soviet atomic bomb were decisive for the notion of the "domino theory", which assumed that the fall of Indochina would cause in rapid succession the collapsed of other nations in Southeast Asia. In 1950, the Truman administration, following its "policy of containment" eventually began to supply France with transport and weapons and increasingly took on the expenditure of the war (in 1954 they financed 80 per cent of the expenses of the war). Although the American government was aware of the fact that there was no other nationalist alternative to Ho Chi Minh the U.S. finally recognized the puppet government headed by the former emperor Bao Dai that the French had appointed whereas the Soviet Union and China recognized the Vietminh to be the legitimate government of Vietnam. In spite of U.S. military assistance and the creation of a Vietnamese National Army by General Jean de Lattre de Tassigny the French only achieved short-range successes and their prospect to eventually win the war deteriorated. At the beginning of 1954, the Vietminh commanded by Vo Nguyen Giap encircled 12,000 French soldiers at the valley around Dien Bien Phu near the border to Laos. President Eisenhower and Secretary of State Dulles refused to authorize an American military strike (there were discussions about an air raid). His plan for a "United Action" in Vietnam based on a broad coalition was rejected by Great Britain. In May of 1954 the French troops at Dien Bien Phu capitulated which sealed the final withdrawal of the French from Indochina.

Nation Building in South Vietnam, 1954-1960

On the occasion of the Geneva Conference (from May to July of 1954), the belligerent powers and other nations representing the West or the East negotiated on a solution. Apart from a cease-fire agreement the Geneva Accords of 1954 planned the temporary partition of Vietnam along the seventeenth parallel surrounded by a demilitarised zone. The French and the Vietnamese fighting under French command were to go south of the demarcation line and the Vietminh would go north. Elections for the reunification of the country were scheduled for 1956 under the supervision of an International Control Committee. Both sides were prohibited from joining a military alliance. Therefore the newly independent Indochinese nations didn't join the SEATO (Southeast Asian Treaty Organization) which was founded in September of 1954 and would legitimate future American intervention in that region.

The U.S. endeavoured to maintain a friendly non-Communist regime in South Vietnam and to prevent a victory of the Communist party through the elections. 14 of 25 millions Vietnamese lived above the seventeenth parallel and Ho Chi Minh had broad popular support in the South as well. When the French had granted independence to the State of Vietnam Ngo Dinh Diem became South Vietnam's prime minister heading a fragile pro-American government. The U.S. not only supported the Diem regime but also committed itself to a major aid program for South Vietnam (more than $1 billion in economic and military assistance from 1955 to 1961). American aid helped the nation to survive its economic crisis and increased the standard of living there, but it also implied Vietnamese dependency on the U.S. Encouraged by the French and Americans about 900,000 northerners, chiefly Catholics, crossed the border to the South that was predominantly Buddhist. The government in Saigon was destabilized by two sects (the Cao Dai and the Hoa Hoa) that were settled in the Mekong Delta maintaining their own armed forces and another organization named the Binh Xuyen with an army of 25,000 men. Diem refused to concede them an autonomous status in their territories which they had during French control. In 1955 his army succeeded in fighting the oppositional forces that had united against him. After solidifying his control over South Vietnam (but still lacking the approval of the population) Diem with American backing blocked the scheduled elections aware of the superiority of the Communists. The United States took on from France, whose forces gradually withdrew from the country, the responsibility for the ARVN (Army of the Republic of Vietnam) and provided a Military Assistance and Advisory Group for its training. Ngo Dinh Diem became increasingly unpopular with the people of South Vietnam by replacing the village councils with Saigon-appointed administrators. By 1956 the regime had incarcerated 20,000 opponents into so-called "reeducation centers" while revolutionary activity in the South was still growing. In 1959, Diem launched a program of forced relocation of the villagers ("agroville" program) in order to protect them from the influence of hostile guerrillas and eventually had to abandon it after spawning opposition among the rural population.

In North Vietnam, the Communist party (Lao Dong) led by Ho Chi Minh had to solve massive reconstruction problems in the years after Geneva. Politically there was a development to a centralist government of the single party organized by the example of the Soviet Union. The Communists carried out a land reform program which already had begun during the war and eliminated all opposition by executing thousands of dissidents until 1956. Subsequently they began a phased collectivisation of the agriculture and the nationalization of the industry. In 1959, the Lao Dong was willing to authorize armed conflicts in the South aiming at the reunification of both parts of Vietnam. Directed by Hanoi, the National Front for the Liberation of South Vietnam was founded by southern revolutionaries in 1960. The NLF not only consisted of Communists, but it was rather a coalition of all those that were in opposition to Diem.

Insurgency and counterinsurgency, 1961-1964

In 1961, infiltration into South Vietnam increased to nearly 4,000 men. The NLF was remarkably successful in recruiting new members and in training them to be guerrillas (also known as "Vietcong", meaning "Vietnam Communist"). They gained control over the villages in the mountainous regions in the western part of South Vietnam and rapidly extended their power southwards.

In reaction, the U.S. government whose president became John F. Kennedy in 1961, authorized a vast increase of American equipment and military advisers (the MAAC was replaced by an enlarged and reorganized Military Assistance and Advisory Group, Vietnam). Kennedy at the first place saw Vietnam narrowly connected with the maintenance of America's credibility which was at risk after the incident at the Bay of Pigs and the commitment to Laos.

The Diem regime attempted to contain the activity of the NLF by means of "counterinsurgency" including the so-called "strategic hamlet program" which stands for the relocation of the peasants into armed villages. That program aimed to protect the villagers from NLF terror and to bind them to the regime through social reforms. But as the hamlets were often established in areas where no security existed, many of them were destroyed by NLF units either by direct attack or by infiltration. Despite of the deployment of helicopters and the involvement of American advisers in combat mission, which was denied in public by the Kennedy administration, the South Vietnamese Army was incapable of weakening the NLF forces. The inferiority of the ARVN showed best in a major battle near the village of Ap Bac in early 1963 when they were inflicted heavy losses though outnumbering the guerrilla companies 10 to 1. The killing of innocent civilians by ARVN soldiers and the use of napalm and defoliants turned more and more people against the government. In May of 1963 government troops fired into crowds of demonstrators in Hue who protested against the prohibition of displaying flags on the anniversary of Buddha's birth. As a result Buddhist leaders accused Diem of religious persecution and the self-immolation of several monks gave rise to mass protests of the disaffected urban population in South Vietnam. A group of ARVN generals secretly contacted the United States reporting on Diem negotiating with Hanoi and inquiring about America's response to an overthrow of the regime. Finally the U.S. abandoned Diem, whom they had supported mainly because of the lack of a political alternative. Although constantly demanding for more American aid Diem had refused to carry out necessary political reforms despite the insistence of the U.S. Diem and his brother Ngo Dinh Nhu were assassinated during a military coup in November of 1963. There are speculations whether President Kennedy intended to extricate America from Vietnam recognizing the futility of its involvement before his assassination in Dallas at the end of 1963.

Desertions from the NLF increased after the overthrow of Diem, who had been the main cause for opposition in South Vietnam, and the NLF lost ground. Consequently the leadership of the Communist party in Hanoi decided to send regular units into the south and to extend infiltration in order to force military operations against the Saigon government. While several unstable administrations followed in quick succession after the coup, anarchy prevailed in South Vietnam's cities where Catholics and Buddhists mobilized against each other. President Lyndon B. Johnson retained the policy of his predecessor realizing to have come to a point where there is no turning back. Besides an increase of economic and military assistance he directed the expansion of covert operations in North Vietnam. Defying firm warnings of the U.S. Hanoi persisted with supporting the insurgency. The North Vietnamese regular army was prepared for war and the Ho Chi Minh Trail was made a modern logistical network. Hanoi's policy may have been based on the premise that its intervention would cause the downfall of Saigon and compel America to withdraw from the country.

Johnson's decisions for war, 1964-1965

On August 2, 1964, a group of North Vietnamese patrol boats encountered the destroyer "USS Maddox" in the Gulf of Tonkin and launched torpedoes after the Maddox had opened fire. Two days later, the Maddox and the "C. Turner Joy" which had been sent to support it, reported being under attack again (an assertion that later would turn out to be false). Secretary of Defense Robert McNamara and his military advisers apparently didn't question the existence of a second attack despite the lack of evidence and consequently Johnson authorized retaliatory air strikes against torpedo boat bases and oil storage facilities in North Vietnam. In addition, the Gulf of Tonkin Resolution almost unanimously passed legislation enabling the president to take "all necessary measures to repel any armed attacks against the forces of the United States and to prevent further aggression". Johnson did not seek to escalate the war at a time of political instability in South Vietnam and therefore no additional attacks on North Vietnamese targets were ordered. He neither responded to an attack on the U.S. air base in Bien Hoa on November 1 with reprisals nor he retaliated when the NLF bombed a U.S. officer's billet in Saigon on Christmas Eve. But at the beginning of 1965 most administration officials, in view of an impending collapse in South Vietnam, agreed that a continuation of the present policies would lead to a defeat of the United States. When on February 6, 1965 NLF units attacked a U.S. Army barracks and a nearby helicopter base in Pleiku, killing nine Americans and destroying five aircraft, the U.S. government decided to strike back. President Johnson ordered the implementation of a plan of reprisal strikes which was drawn up by the Joint Chiefs of Staff (JCS) called "Flaming Dart". After the NLF had raided another U.S. military installation at Qui Nhon, even more aerial attacks followed. Soon Washington proceeded with initiating "Rolling Thunder", a program of continuing, gradually intensified air raids on North Vietnam. In anticipation of retaliatory attacks for Rolling Thunder, General William C. Westmoreland urged the posting of a small number of American combat troops to protect the air base at Danang. Not aware that this would violate an unwritten rule the American Indochina policy so far had kept to Johnson approved his request and on March 8 two battalions of Marines landed near the city. Shortly after the administration decided on a deployment of some 40,000 additional U.S. ground combat forces in Vietnam besides the maintenance of the bombing campaign laying the foundations of a large-scale American involvement in the ground war. Johnson and his government continuously misled their nation about the nature of their troops' mission. It had moved from the original objective of base security to offensive operations due to the militarily and politically worsening situation in South Vietnam and the slow pace of the ARVN buildup. The expansion of war gave rise to criticism among the students, the media, and even Democratic senators advocated a peace settlement. Johnson met increasing criticism by a series of counterinitiatives to defend his policy and by a token offer to participate in peace negotiations.

In South Vietnam, Air Marshal Nguyen Cao Ky becoming the prime minister and General Nguyen Van Thieu commanding the armed forces came into power. It was already the fifth government since the death of Diem. The ARVN had to record a high desertion rate and was on the edge of disintegration leaving the military responsibility to the Americans. The NLF supported by North Vietnamese regular forces inflicted crushing defeats on the ARVN in major battles in the Central Highlands and north of Saigon. Westmoreland and the JCS one more time made demands on Johnson for the provision of additional combat forces to avert defeat. Johnson was seeking for a middle course between a total war that involved the danger of a Chinese intervention and a withdrawal whose domestic consequences he feared. In July of 1965 he authorized the use of B-52s and the intensification of the bombing as well as the immediate deployment of 50,000 troops and of additional forces later as the situation would demand it. By the end of 1965, 180,000 Americans were serving in South Vietnam under the command of General Westmoreland.

The beginnings of the American Vietnam War, 1965-1967

Between 1965 and 1967 the United States massively extended the air war raising the number of sorties and bombs to a multiple. In the beginning Rolling Thunder was mainly targeted on military bases, supply depots and infiltration routes in the south but from 1966 on the air raids steadily moved northward up to the Chinese border being directed against North Vietnamese industrial and transportation systems. The bombing inflicted great damage on the developing nation of the Democratic Republic of Vietnam (DRV) and demanded a thousand civilian casualties per month. Despite high expenditures and the devastation caused by the B-52s, the bombing campaign did not reach its goals. Although areas leading to the Ho Chi Minh Trail were continuously attacked, infiltration into the south amounted to 90,000 in 1967. North Vietnam was remarkably skilful in evacuating the urban population, rebuilding traffic routes and in digging a vast tunnel system. In addition, the DRV was able to compensate for its material losses with increased aid from China and the Soviet Union. The two Communist powers did not settle their differences in view of the escalation of the U.S. but they were played off against each other by Hanoi. The new Soviet leaders Brezhnev and Kossygin who succeeded Khrushchev in 1964 paid more attention to the Vietnam conflict and provided North Vietnam with sophisticated military equipment. Soviet surface-to-air missiles and MIG fighters generated an effective air defense system around the cities of Hanoi and Haiphong. Beijing agreed to detail 320,000 engineering and artillery troops and additionally to provide equipment for the North Vietnamese Army (NVA).

General Westmoreland who bore the responsibility for American ground war operations relied on a strategy of attrition, which aimed at locating and eliminating NLF and NVA units and would be called "search and destroy". Initial optimism was based on the belief that the application of America's technological superiority would automatically lead to its victory. But Westmoreland's aggressive strategy neglected to adjust to the enemy's guerrilla warfare (such as ambushes and hit-and-run operations) and constantly required the deployment of additional troops which is why the U.S. requested its Pacific allies to commit forces (and thus give the war international respectability). Except for South Korea which provided 60,000 troops, the allies made only limited commitments whereas American troops increased to 485,000 by the end of 1967. Increasingly American combat forces took it upon to wage the actual war whereas the ARVN was assigned defensive operations and population control. At the beginning American tactics in fact proved to be successful when NLF forces sustained considerable losses during heavy fighting in the province of Quang Ngai and at Ia Drang Valley in late 1965. The bombs dropped on South Vietnam exceeded double the tonnage of bombs of the air war in the north and the use of herbicides such as "Agent Orange" destroyed half of South Vietnam's forests. Entire areas in the south were designated "Fire Free Zones" as for instance when in 1967 during the operation "Cedar Falls" a NLF stronghold north of Saigon named the Iron Triangle was virtually levelled with the ground. As there were no front lines excepting the demilitarised zone, where North Vietnamese and American forces faced in static warfare, the "body count" and the "kill ratio" became the index of success. The figures of enemy casualties were distorted by a great number of dead civilians and it is known that statistics often based on the attitude "If it's dead and it's Vietnamese, it's Vietcong".

After the Buddhists anew initiated demonstrations in Hue and Saigon against the Ky regime and American domination, the U.S. arranged a Revolutionary Development Program to pacify the villages. The program, in which RD teams that were trained in social services and propaganda should undermine NLF guerrillas and make the villagers support the government, eventually proved to be a failure as well as American efforts for a new constitution and elections in South Vietnam. When in September of 1967 elections were held, the ticket of Thieu and Ky, who ran for the vice presidency, won 35 per cent of the vote.

The Tet Offensive: a turning point (1968)

On January 30, 1968 (the day of the Vietnamese lunar new year named Tet), nineteen NLF sappers forced their way into the U.S. embassy where they held their position for six hours until they were finally overwhelmed and all killed or severely wounded. At the same time some 80,000 NLF guerrillas assaulted the major South Vietnamese cities and towns including an airport, the presidential palace and the headquarters of South Vietnam's general staff in Saigon. The Tet Offensive referred to Hanoi's decision in mid-1967 to employ a different strategy in view of its enormous casualty rate, the restriction of guerrilla warfare owing to the influx of refugees into the cities and the devastation dealt out through the air war. The new strategy conducted by General Giap consisted of diversionary attacks in remote areas to lure American troops away from the population centres which afterwards would be the objective of guerrilla assaults. The surprise attacks were preceded by the siege of a base of marine infantrymen at Khe Sanh by two North Vietnamese divisions on January 21. To avoid a repetition of Dien Bien Phu Westmoreland concentrated about 50,000 troops to defend the garrison and B-52s carried out the most densely applied bombardments in history. Despite preoccupation with Khe Sanh and Tet traditionally being observed a time of cease-fire the ARVN in conjunction with American forces was able to hold off the initial attacks (with the exception of Hue which was held for several weeks). The NLF was all over heavily decimated, in all it sustained 33,000 casualties. Moreover, the Tet campaign created one million new refugees. From 1968 on, the majority of the insurgents in South Vietnam were actually North Vietnamese soldiers who had infiltrated into the south.

The plan of the North Vietnamese and the NLF to arouse a general uprising had failed and thus the offensive represented a military defeat for them but it had an enormous impact on public opinion in America. From many people's and politicians' point of view the war was going to lead to an open-ended commitment. The Tet attacks and following requests for additional 200,000 troops contradicted the previous optimistic pronouncements. Consequently the reporting of the media shifted to a more critical position. Already by 1967, at a time when Americans were questioning their value and institutions, Vietnam turned out to be the most divisive war ever, disuniting the people between the extremes of "hawks" and "doves". Criticism ranged from reproaches for inefficiency to immorality of the war and the ones in Washington that were pulling the strings. The use of weapons such as cluster bombs, herbicides and napalm, the killing of an estimated 1,000 non-combatants per week, the fact that the U.S. was supporting a corrupt and authoritarian government in South Vietnam, the apparent irrelevancy of Vietnam to the security of the U.S. and the increasing financial burden raised anti-war sentiment. It expressed itself in peace marches, demonstrations and thousands of draftees trying to evade the draft by fleeing to Canada or applying other methods. After permanent unsuccessfulness Lyndon Johnson and Robert McNamara themselves appeared to be disillusioned. Nevertheless the President was unwilling to abandon his original goals and to accept defeat. In Vietnam, tensions grew between American and South Vietnamese troops because of differences of culture and mutual incomprehension. In March of 1968, an American company under the command of Lieutenant William Calley committed the massacre of My Lai by murdering the small hamlet's 500 inhabitants, including women and children.

On March 31 Johnson announced in a televised address that the bombing north of the 20^th parallel would be stopped and that he would not seek re-election for another term as president. By that Johnson initiated a process of de-escalation on both sides. The United States and the DRV agreed to begin preliminary peace talks in Paris, and in October Johnson ordered a total bombing halt. Already before, General Creighton Abrams had replaced Westmoreland in commanding the U.S. ground forces in South Vietnam.

Nixon and Vietnamization, 1969-1971

President Richard M. Nixon and Henry Kissinger, whom he had appointed national security advisor, realized that the war was to be brought to an end soon, but nevertheless they insisted on what they called an "honourable peace" (which meant a settlement that secured the independence of South Vietnam in future). The U.S. adopted a plan of phased withdrawal known as "Vietnamization", whereby the ARVN would gradually assume all military responsibilities while being reinforced with American arms ( more than a million M-16 rifles) and equipment. Military schools were expanded in order to augment the ARVN force level and efforts to modernize the promotion system and to improve conditions for South Vietnamese soldiers aimed to check the desertion rate. In 1969, an "Accelerated Pacification Program" was institutionalised to extend government control over the countryside, in the course of which the autonomy of the villages was restored and their security was improved by 500,000 regulars assigned to pacification. By gradually withdrawing U.S. troops from Vietnam, Nixon overrode voices like Abrams' who doubted that the Thieu government and its combat forces could without American assistance detain the "Vietcong" combined with NVA forces and thus a Communist takeover. Simultaneously with Vietnamization, the President who counted on his reputation as a hard-line anti-Communist, intended compelling Hanoi to negotiate on his terms through threats of massive force. Operation "Menu", a series of (secret) bombing raids against North Vietnamese sanctuaries, broadened the war into neutral Cambodia. Eventually during the spring of 1970, after Cambodia's neutralist Prince Sihanouk was overthrown by a pro-American clique headed by Prime minister Lon Nol, U.S. and ARVN troops invaded border sectors of Cambodia. Nixon announced in a television speech that the real target of the Cambodian incursion was the North Vietnamese "Central Office for South Vietnam", although the Defense Department did not know for certain where it was located or whether it even existed. The invasion resulted in a brutal civil war between the Khmer Rouge insurgents (supported by the DRV) and the Cambodian government of Lon Nol, which was recognized and supported on a large scale by the United States. Nixon's expansion of the war sparked a new wave of anti-war demonstrations among the students, and at Kent State University and Jackson State College six students were killed in confrontations with the National Guardsmen and the police, which again produced massive protests in Washington in May of 1970. To appease the increasing critics in America, the President pushed his withdrawal policy, reducing military personnel in Vietnam to 175,000 by the end of 1971. At the same time, he intensified military pressure against North Vietnam by approving of a major ground operation into Laos in February of 1971 (carried out by the ARVN with U.S. air support), the objective of which was to gain time for Vietnamization by destroying enemy supply lines. Meanwhile, the trial against Lieutenant William Calley, in which he was sentenced to life imprisonment by a military court, and the publication of the so-called "Pentagon Papers" (a secret government study of U.S. involvement in southeast Asia covering the period from World War II to 1968) caused a continuation of protests and demonstrations, that were, among others, sustained by the newly formed "Vietnam Veterans Against the War".

The peace talks between Kissinger and North Vietnamese negotiator Le Duc Tho in Paris remained inconclusive. North Vietnam insisted on demands for a complete withdrawal of U.S. troops from Vietnam, the abandonment of Thieu and a provisional coalition government to his exclusion. The American administration, however, refused to disassociate itself from Thieu, who was re-elected in September of 1971, and moreover the U.S. demanded the release of the American prisoners of war. After having fought for their goals for more than ten years, neither side was willing to make the necessary concessions, and both still felt that they were able to force the enemy by military means to give in.

The end of the American commitment / Vietnam in the aftermath of the war, 1972-1975

In March 1972, North Vietnam launched a massive invasion of the south by sending 120,000 NVA troops, spearheaded by Soviet tanks, across the demilitarised zone. The offensive was aimed directly at the ARVN's main forces and focused on the cities of the Quang Tri province, Kontum in the Central Highlands, and An Loc to the north of Saigon. At that time only 95,000 U.S. forces remained there, 6,000 of them combat troops, and the leadership of the DRV was aware that if Nixon sent American ground forces back to Vietnam, that would have grave domestic consequences. Moreover, the United States implemented a policy of détente through secret negotiations with China and the USSR and finally Nixon and Soviet Premier Leonid Brezhnev signed the Strategic Arms Limitation Treaty at a summit conference in Moscow in May. Washington decided to strike back with Operation "Linebacker", which consisted of the mining of Haiphong harbour, a naval blockade of North Vietnam and intense bombing attacks in the Hanoi-Haiphong area, thereby cutting off North Vietnamese resupply of fuel and ammunition. The campaign of the summer of 1972 claimed a high casualty rate on both sides, (the North Vietnamese losing an estimated 100,000 men and the South Vietnamese 25,000), but it didn't change the military stalemate in Vietnam. Peace negotiations broke down in mid-December, and during the next twelve days the north was once again subjected to intensive U.S. bombing.

On January 27, 1973, the Paris talks eventually resulted in an agreement between North Vietnam, the South Vietnamese communist forces, the USA and South Vietnam. The peace accords included an immediate cease-fire, the cessation of all U.S. military activities against the DRV by ground, air or naval forces, the withdrawal of all American troops and military personnel as well as the dismantlement of U.S. military bases in South Vietnam within sixty days. In addition, the agreement planned to stop American invention into South Vietnam's internal affairs, to re-establish the military demarcation line at the 17^th parallel as a provisional boundary until the reunification of the country by peaceful means and to return American prisoners of war.

Although the two chief negotiators Henry Kissinger and Le Duc Tho were awarded the Nobel Peace Prize in 1973 for achieving a cease-fire agreement, the treaty should turn out not to be worth the paper it was printed on. North Vietnam still sought unification of the country on its terms whereas South Vietnam struggled to survive as an independent nation. The war in Vietnam continued without direct participation of the United States in its last phase. By the end of march, all U.S. troops had been withdrawn, (of which 58,000 had been killed during the war, more than 300,000 wounded and an indefinite number remained missing in action), but American naval power and air force remained in the Gulf of Tonkin and in Thailand and Guam as well as American economic and military aid for South Vietnam was maintained. In order to gain additional territory and to solidify his position in the south, Thieu resettled refugees and built forts in contentious areas, attacked North Vietnamese bases and supply lines and villages that were controlled by the Provisional Revolutionary Government (PRG, created by the NLF as an opposition to the Government of Viet-Nam). Meanwhile, the North Vietnamese adopted a wait-and-see policy, infiltrated troops and equipment into the south and extended their logistical network. When in late 1973 Thieu launched an offensive against enemy bases and PRG territories, the Politburo in Hanoi authorized NLF forces to engage in armed conflict. As Nixon's (whom the Watergate scandal forced to resign in August 1974) and Kissinger's arguments for support of the GVN did no longer pass a more and more reluctant Congress, the U.S. drastically cut its military aid in 1974, aggravating the political and economical crisis in South Vietnam. By the fall of that year, the military balance had shifted in favour of North Vietnam and the NLF. After a successful attack on Phuoc Binh (a provincial capital nearby Saigon) in December 1974, the Communists planned for a series of large-scale offensives during the next two years. Accordingly, combat forces commanded by North Vietnamese chief of staff General Van Tien Dung launched an offensive in the Central Highlands in March 1975, which would initiate the collapse of South Vietnam. After the rapid fall of Pleiku and Kontum, Thieu ordered a withdrawal from the highlands which resulted in the capture or destruction of large parts of the ARVN and the death of thousands of civilians. When the North Vietnamese forces advanced on Hue and Danang, the defending army disintegrated and, along with hundreds of thousands of civilians, created a stream of refugees towards Saigon. Gradually, the coastal cities were abandoned and, after Congress had rejected Gerald Ford's request for aid and at Xuan Loc, the only location where the ARVN was able to offer resistance, President Thieu resigned on April 21, 1975. The South Vietnamese government unconditionally surrendered on April 30 in Saigon, that afterwards was renamed Ho Chi Minh City. On July 2, 1976 the country was officially reunited as the Socialist Republic of Vietnam.