The Domino Theory

domino theory

Falling dominos

The Domino Theory was the belief that communism was an aggressive, expanding imperialism that would spread from one country to the next, until it dominated the world. This idea shaped US and Western foreign policy during the Cold War, particularly with regard to Asia. Communist ideology itself contained some evidence to validate this argument. The writings of Russian Bolshevik leader Vladimir Lenin called for ‘international revolution’. Communism, he said, was a movement based on class, not nationality or race. It would transcend borders, nationalities, patriotism and language barriers. Once communism had taken hold in Russia, Lenin believed it would inspire similar revolutions in Germany, France and other European nations. Wherever workers were being exploited and oppressed, communism would flourish. The new Soviet government played a leading role in advancing this international revolution. In March 1919 Moscow established the Communist International, or Comintern, a committee of Russian and foreign delegates. The Comintern’s main objective was to promote and advance communist movements abroad, to facilitate the ‘world revolution’. The Comintern was attended by delegates from communist parties in dozens of countries, including Western nations like the United States, Great Britain and Australia. In its early years the Comintern provided training and material support to individuals and groups around the world, including the Chinese Communist Party (CCP) and Vietnamese nationalist Ho Chi Minh.

The Domino mindset

domino theory

A Soviet image of Lenin ‘cleaning the world’

The West had long been paranoid about the internationalist agenda of communism. This paranoia hardened into the Domino Theory in the late 1940s, on the back of Stalin’s expansion into eastern Europe and the rise of communism in China. Western leaders came to believe that once communism gained a foothold in one nation, neighbouring countries would soon be infiltrated, overrun and seized by communists – much like a row of standing dominos topples, one knocking over the next until they have all fallen. It is not known who first used the analogy of falling dominos or coined the phrase Domino Theory. The first public mention of it was made by US president Dwight Eisenhower in a speech in 1954, where he explained why America would aid the French in their struggle against communists in Indochina (Vietnam):

[There are] broader considerations that might follow what you would call the ‘falling domino’ principle. You have a row of dominoes set up, you knock over the first one, and what will happen to the last one is the certainty that it will go over very quickly… But when we come to the possible sequence of events, the loss of Indochina, of Burma, of Thailand, of the Peninsula (Malaysia and Singapore) and Indonesia following, now you begin to talk about … millions and millions and millions of people.

This readiness to accept the Domino Theory was probably influenced by events in Europe during the 1930s. Most Cold War politicians and foreign policy planners had lived through the pre-war period, when central European regions – the Rhineland, Austria, the Sudetenland and Czechoslovakia – had all fallen to Hitler, one after another. The policy of appeasement – letting Hitler annex or seize particular regions in the hope it would satisfy him – had failed to prevent war. There was a similar scenario in Asia, where Japanese imperial expansion was allowed to spread unchecked through the 1930s. The attitudes of Cold War leaders were shaped by these events, and these attitudes made them more determined to act against perceived aggression and expansion. As historians Leslie Gelb and Richard Betts put it:

The domino theory … resulted from thinking along the lines of some simple, albeit appealing, psychological and legal analogies. If you let your daughter come home late from a date without punishment, the next thing you know she will be pregnant. If you let a crime go unpunished, you invite more crime. If aggression is tolerated in small out-of-the-way places, aggressors will be emboldened to attack larger, more vital places. US leaders saw a straight line from the Japanese takeover of Manchuria in 1931 to the invasion of China to the invasion of Indochina to the attack on Pearl Harbour. Once the principle has been undermined, there is no stopping place.

Asia, a fertile ground for communists

domino theory

A map predicting the spread of communism in Asia

An additional factor in the Domino Theory was concern that many nations were incapable of resisting communism – particularly if it was to take hold in their region. Most European nations were fatigued and economically exhausted after years of war. Their governments were weak and their people depressed, desperate and starving. This made them easy prey to communist infiltration and propaganda. Asia was just as susceptible to communist incursion. The governments and military forces of most Asian nations were comparatively weak. Their populations contained large numbers of peasants, who were susceptible to communist propaganda and recruitment. Nationalist and independence movements in Asia were considered ideal ‘hiding places’ for communist infiltrators. Asian borders were not well policed and were largely insecure, so communists could move in and out of target countries with ease.

“Two generations of presidents and officials had lived through or were reared on the dominos of the 1930s. Whatever their exact circumstances and consequences, these cases came to possess a simple and compelling message: if aggression is tolerated in small, out-of-the-way places, aggressors will be emboldened to attack larger, more vital places. US leaders saw straight lines from the Japanese takeover of Manchuria in 1931 to the invasion of China to the invasion of Indochina to the attack on Pearl Harbour. They saw the straight line from Italy’s attack on Ethiopia in 1935 to German re-occupation of the Rhineland to the anchluss of Austria to the rape of Czechoslovakia at Munich to general war in Europe.”
Leslie H. Gelb, historian

The Domino Theory was also underpinned by assumptions about Chinese expansion. Western planners believed that China would act as a vanguard for advancing communism in Asia, much as Soviet Russia had done in eastern Europe. The events of the late 1940s and 1950s seemed to support this. Chinese troops supported the communist invasion of South Korea during the Korean War (1950-53). During the same period Beijing was providing moral, material and logistic support to Ho Chi Minh and the emerging Viet Minh in northern Vietnam. As Chinese economic and military capacity increased, the West believed China would export communism to create a buffer between itself and potential threats. This placed a number of countries at risk of communist aggression, including South Korea, Vietnam, Taiwan, Japan, the Philippines, Thailand, Burma, Tibet, Malaya, Singapore and Indonesia.

‘Piece by piece, country by country’

domino theory

A cartoon depicting the ‘falling dominoes’ of Asia

Every US president from the late 1940s to the early 1970s was an advocate of the Domino Theory. Though Harry Truman never used the domino analogy, he accepted its general principles nonetheless and used it as the basis of his Truman Doctrine. John F. Kennedy spoke of the Domino Theory and hinted at it in his inauguration speech, when he warned that “our security may be lost piece by piece, country by country.” Lyndon Johnson and Richard Nixon also accepted the Domino Theory as fact, underpinning their decision to escalate and remain involved in the Vietnam War. The costly American defeat in Vietnam saw the Domino Theory largely discredited. Today, it remains a controversial idea with its detractors generally outnumbering its supporters. Some claim the Domino Theory was entirely valid and proved correct by the southward march of communism into Asia; only US intervention in Asia halted its progress. Others argue that it was a simplistic theory which failed to acknowledge that Asian communism was motivated by nationalism as much as by the push for ‘world revolution’.





1. The Domino Theory was the belief that communism was spread from one nation to its neighbours, and so on.
2. It was based on an analogy with falling dominos, was popularised in the 1950s and became widely accepted.
3. The theory was partly supported by the Soviet-led Comintern, which promoted communism around the world.
4. Asia was considered to be particularly susceptible to communism, as its governments and borders were weak.
5. The Domino Theory was accepted as fact by all US presidents during the Cold War and became an underlying principle in American foreign policy.

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This page was written by Jennifer Llewellyn, Jim Southey and Steve Thompson. To reference this page, use the following citation:
J. Llewellyn et al, “The Domino theory”, Alpha History, accessed [today’s date],