On 11 November 1960, a failed coup attempt against President Ngô Đình Diệm of South Vietnam was led by Lieutenant Colonel Vương Văn Đông and Colonel Nguyễn Chánh Thi of the Airborne Division of the Army of the Republic of Vietnam (ARVN).
The rebels launched the coup in response to Diệm's autocratic rule and the negative political influence of his brother Ngô Đình Nhu and sister-in-law Madame Nhu. They also bemoaned the politicisation of the military, whereby regime loyalists who were members of the Ngô family's covert Cần Lao Party were readily promoted ahead of more competent officers who were not insiders. Đông was supported in the conspiracy by his brother-in-law Lieutenant Colonel Nguyen Trieu Hong, whose uncle was a prominent official in a minor opposition party. The main link in the coup was Đông's commanding officer Thi, whom he persuaded to join the plot.
The coup caught the Ngô family completely off-guard, but was also chaotically executed. The plotters neglected to seal the roads leading into the capital Saigon to seal off loyalist reinforcements, and they hesitated after gaining the initiative. After initially being trapped inside the Independence Palace, Diệm stalled the coup by holding negotiations and promising reforms, such as the inclusion of military officers in the administration. In the meantime, opposition politicians joined the fray, trying to exploit Diệm's position. However, the president's real aim was to buy time for loyalist forces to enter the capital and relieve him. The coup failed when the 5th and 7th Divisions of the ARVN entered Saigon and defeated the rebels. More than four hundred people—many of whom were civilian spectators—were killed in the ensuing battle. These included a group of anti-Diệm civilians who charged across the palace walls at Thi's urging and were cut down by loyalist gunfire.
Đông and Thi fled to Cambodia, while Diệm berated the United States for a perceived lack of support during the crisis. Afterwards, Diệm ordered a crackdown, imprisoning numerous anti-government critics and former cabinet ministers. Those that assisted Diệm were duly promoted, while those that did not were demoted. A trial for those implicated in the plot was held in 1963. Seven officers and two civilians were sentenced to death in absentia, while 14 officers and 34 civilians were jailed. Diệm's regime also accused the Americans of sending Central Intelligence Agency members to assist the failed plot. When Diệm was assassinated after a 1963 coup, those jailed after the 1960 revolt were released by the new military junta.
Background
The revolt was led by 28-year-old Lieutenant Colonel Vương Văn Đông, a northerner, who had fought with the French Union forces against the Viet Minh during the First Indochina War. Later trained at Fort Leavenworth in the United States, Đông was regarded by American military advisers as a brilliant tactician and the brightest military prospect of his generation and he served in the Airborne Division. Back in Vietnam, Đông became discontented with Diệm's arbitrary rule and constant meddling in the internal affairs of the army. Diệm promoted officers on loyalty rather than skill, and played senior officers against one another in order to weaken the military leadership and prevent them from challenging his rule. Years after the coup, Đông asserted that his sole objective was to force Diệm to improve the governance of the country. Đông was clandestinely supported by his brother-in-law Lieutenant Colonel Nguyen Trieu Hong, the director of training at the Joint General Staff School, and Hong's uncle Hoang Co Thuy. Thuy was a wealthy Saigon-based lawyer, and had been a political activist since World War II. He was the secretary-general of a minority opposition party called the Movement of Struggle for Freedom, which had a small presence in the rubber-stamp National Assembly.
Many Army of the Republic of Vietnam (ARVN) officers were members of other anti-communist nationalist groups that were opposed to Diệm, such as the Đại Việt Quốc dân đảng (Nationalist Party of Greater Vietnam) and the Việt Nam Quốc Dân Đảng (VNQDĐ, Vietnamese Nationalist Party), which were both established before World War II. The VNQDĐ had run a military academy in Yunnan near the Chinese border with the assistance of their nationalist Chinese counterparts, the Kuomintang. Diệm and his family had crushed all alternative anti-communist nationalists, and his politicisation of the army had alienated the servicemen. Officers were promoted on the basis of political allegiance rather than competence, meaning that many VNQDĐ and Đại Việt trained officers were denied such promotions. They felt that politically minded officers, who joined Diệm's secret Catholic-dominated Cần Lao Party, which was used to control South Vietnamese society, were rewarded with promotion rather than those most capable.
Planning for the coup had gone on for over a year, with Đông recruiting disgruntled officers. This included his commander, Colonel Nguyễn Chánh Thi. In 1955, Thi had fought for Diệm against the Bình Xuyên organised crime syndicate in the Battle for Saigon. This performance so impressed Diệm—a lifelong bachelor—that he thereafter referred to Thi as "my son". However, the Americans who worked with Thi were less impressed. The CIA described Thi as "an opportunist and a man lacking strong convictions". An American military advisor described Thi as "tough, unscrupulous, and fearless, but dumb". There is some dispute as to whether Thi participated in the coup of his free choice. According to some sources, Thi was still an admirer of Diệm and was forced at gunpoint by Đông and his supporters to join the coup at the last minute, having been kept unaware of the plotting. According to this story, Thi's airborne units were initially moved into position for the coup without his knowledge.
Many months before the coup, Đông had met Diệm's brother and adviser Ngô Đình Nhu, widely regarded as the brains of the regime, to ask for reform and de-politicisation of the army. Đông said that the meeting went well and was hopeful that Nhu would enact change. However, a few weeks later, Dong and his collaborators were transferred to different commands and physically separated. Fearing that Diệm and Nhu were trying to throw their plans off balance, they accelerated their planning work, and decided to move on October 6. However, they were then scheduled to go into battle against the Viet Cong (VC) near Kon Tum in the II Corps in the Central Highlands, forcing a postponement. According to the historian George McTurnan Kahin, Đông was without a command by the time the coup was held.
The Americans started to notice and become alarmed at increasing reports of political disillusionment in the military officer corps in August. An intelligence report prepared by the US State Department in late August claimed the "worsening of internal security, the promotion of incompetent officers and Diệm's direct interference in army operations ... his political favoritism, inadequate delegation of authority, and the influence of the Can Lao". It also claimed that discontent with Diệm among high-ranking civil servants was at their highest point since the president had established in power, and that the bureaucrats wanted a change of leadership, through a coup if needed. It was said that Nhu and his wife were the most despised among the civil service. The report predicted that if a coup was to occur, the objective would probably be to force Nhu and his wife out of positions of power and allow Diệm to continue to lead the country with reduced power, should he be willing to do so. The intelligence analysis turned out to be correct.
The US Ambassador Elbridge Durbrow, who had been in the post since 1957, had a long record of trying to pressure Diệm into political reforms. He felt that South Vietnam's political problems were due to Diệm's illiberalism and thought the communist insurgency would be more easily defeated if Diệm reached out to a broader cross-section of society, cracked down on corruption, cronyism, abusive public servants, and implemented land reform. However, the South Vietnamese president saw authoritarianism as the solution to political problems and opposition, and the US military hierarchy in Vietnam agreed, leading to frequent disputes between Durbrow and the Military Assistance Advisory Group (MAAG). Durbrow frequently reported to Washington that Diệm's strong-arm tactics against opposition only created more dissent and opportunities for the communists.
Around this time, Durbrow began to advise Diệm to remove Nhu and his wife from the government, basing his arguments on a need to cultivate broad popular support to make South Vietnam more viable in the long term. His key suggestions included Nhu being sent abroad as an ambassador, removing Nhu's wife and intelligence director Tran Kim Tuyen from public power and sending them overseas, new defense and interior ministers, and "altering the nature of the Cần Lao Party" to acknowledge its existence and operations in public. These proposals were endorsed by the State Department and delivered to Diem. As Nhu and the Can Lao were a core means of his keeping power, Diệm did not follow Durbrow's advice, and was reported to have become angry when Durbrow suggested that corruption and political favoritism was diminished the government's effectiveness.
On September 16, after another fruitless meeting with Diệm, Durbrow reported to Washington: "If Diệm's position in [the] country continues to deteriorate ... it may become necessary for [the] US government to begin consideration [of] alternative courses of action and leaders in order [to] achieve our objective." In another State Department Report, it was concluded that a coup would become more likely "if Diệm continued to remain uncompromising and if the opposition felt that the United States would not be unsympathetic to a coup or that U.S.–Vietnamese relations would not be seriously damaged." As it turned out those in Vietnam discontented with Diệm reached the same conclusion, that the US would not mind them toppling the president.
The coup was organised with the help of some VNQDĐ and Đại Việt members, civilians and officers alike. Đông enlisted the cooperation of an armoured regiment, marine unit and three paratrooper battalions. The marine battalion was commanded by Lieutenant Colonel Phạm Văn Liễu. The operation was scheduled to launch on 11 November at 05:00. However, the airborne soldiers were not aware of what their officers had in store. They were told that they were heading into the countryside to attack the VC. Once they were on their way, the officers claimed that the Presidential Guard, who were meant to guard the presidential palace, had mutinied against Diệm.
Coup
According to Stanley Karnow, the Pulitzer Prize-winning author of Vietnam: A History, the coup was ineffectively executed; although the rebels captured the headquarters of the Joint General Staff near Tan Son Nhut Air Base, they failed to follow the textbook tactics of blocking the roads leading into Saigon. While they captured Saigon's principal telephone exchange at the central post office, they failed to secure a secondary system that was located in the basement. This meant that phone lines into the palace remained intact, which allowed Diệm to call for aid from loyal units. Most notably, the director of the post office, who remained loyal, was able to call Diem's director of intelligence Tran Kim Tuyen, allowing him to summon loyalist forces.
The paratroopers headed down the main thoroughfare of Saigon towards Independence Palace. At first, the forces encircled the compound without attacking, believing that Diệm would comply with their demands. Đông attempted to call on US ambassador Durbrow to put pressure on Diệm. Durbrow, although a persistent critic of Diệm, maintained his government's position of supporting Diệm, stating "We support this government until it fails". Durbrow later recalled receiving a telephone call from an aide to Diệm who insisted that he call Diệm and tell him to surrender or face a howitzer attack on the palace. Durbrow refused and no attack took place. He consequently learned that the aide was forced to make the call.
Most of the rebel soldiers had been told that they were attacking in order to save Diệm from a mutiny by the Presidential Guard. Only one or two officers in any given rebel unit knew the true situation. A high wall, a fence and a few guard posts, surrounded the palace grounds. The mutinous paratroopers disembarked from their transport vehicles and moved into position for an attack on the main gate. Some ran forward and others raked automatic gunfire at the front of the palace, shattering most of the windows and puncturing the walls. Diệm was nearly killed in the opening salvoes. A rebel machine gun fired into Diệm's bedroom window from the adjacent Palais de Justice and penetrated his bed, but the president had arisen just a few minutes earlier.
The paratroopers' first assault on the palace met with surprising resistance. The Presidential Guardsmen who stood between the rebels and Diệm were estimated at between 30 and 60, but they managed to repel the initial thrust and kill seven rebels who attempted to scale the palace walls and run across the grass. The rebels cordoned off the palace and held fire. They trucked in reinforcements and the attack restarted at 7:30, but the Presidential Guard continued to resist. Half an hour later, the rebels brought in five armored vehicles and circumnavigated the palace. They fired at the perimeter posts, and mortared the palace grounds. However, the exchange had petered out by 10:30. In the meantime, the rebels had captured the National Police offices, Radio Saigon and the Cộng Hòa barracks of the Presidential Guard. They had also put most of the Saigon-based generals under house arrest, meaning that Diệm's saviours would have to come from outside Saigon. However, the rebels also suffered a setback when Hong was killed during the battle for the police headquarters. He had been sitting in his jeep behind the frontline when he was hit by stray gunfire.