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Truman Doctrine

The Truman Doctrine is commonly referred to as one of the starting pistols for the Cold War, cementing the deterioration of relations between the United States and the Soviet Union after the Second World War. But what led to the change in US foreign policy? And what did the Truman Doctrine promise? Let's find out!

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Truman Doctrine


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The Truman Doctrine is commonly referred to as one of the starting pistols for the Cold War, cementing the deterioration of relations between the United States and the Soviet Union after the Second World War. But what led to the change in US foreign policy? And what did the Truman Doctrine promise? Let's find out!

The Truman Doctrine was announced by President Harry Truman on 12 March 1947. It was a pledge made by the United States to support countries with a new, hardline foreign policy against the spread of communism. It specified the financial support granted by the US to Greece and Turkey amidst their struggles against communism.

It is important to examine the background causes that led to President Harry Truman's harder stance against communism to understand the reasons for the Truman Doctrine.

Causes of the Truman Doctrine

Towards the end of the Second World War, the USSR liberated a large proportion of Eastern European countries from the Axis powers. However, the Soviet Red Army continued to occupy these countries after the war and pressured them to come under the USSR's sphere of influence. Let's look at how the Soviet policy of communist expansionism affected relations with the US, and then see how this relates to Greece and Turkey.

Soviet Expansionism

On 22 February 1946, George Kennan, the US Ambassador in Moscow, sent a telegram to the Secretary of State detailing his informed opinions on USSR policy. He states:

The USSR still lives in antagonistic "capitalist encirclement" with which in the long run there can be no permanent coexistence.1

Kennan continued, claiming that the Soviet Union would not form a lasting alliance with capitalist countries.

They have learned to seek security only in patient but deadly struggle for total destruction of rival power, never in compacts and compromises with it.2

Kennan's warning was against Soviet expansionism after the Second World War. In particular, Kennan foresaw Turkey and Iran as the USSR's immediate targets for communist uprisings and joining their sphere of influence.

By providing a detailed and informed analysis of Stalin's leadership and projections for the USSR's expansion, Kennan's report confirmed for Truman that a change in US foreign policy was needed to stop the spread of communism.

Greek Civil War

The Greek Civil War (1943-49) itself was not a reason for the Truman Doctrine but the events in Greece demonstrated Kennan's assessment of the spread of communism throughout Europe after WWII. Let's look at a brief overview of the political atmosphere in Greece at this time.

The truman Doctrine greek pro-monarchist poster studysmarterThis poster advocates the Greek Monarchy during the Civil War, driving out the threatening Communist representatives. Source: Wikimedia Commons


1941-1944Axis powers occupy Greece during WWII. Over 100,000 Greeks died from starvation as a result. Underground guerrilla communist groups form a key part of Greek resistance.
October 1944Britain liberates Greece from Nazi control and establishes an unstable coalition government between the rivalling Monarchist and Communist parties.
1944-1945The first stage of the Greek Civil War between the Monarchists and the Communists. The Monarchists are supported by Britain and win. The Greek Communist Party disbands in 1945.
1946The Communist Party reforms and begins the second stage of the Greek Civil War.
Early 1947Britain withdraws its support from Greece as it was suffering economically after WWII and Greek civil unrest was becoming too expensive to handle.
12 March 1947The Truman Doctrine is announced. Greece receives $300 million and US military support in the war against the Communists.
1949Second stage of the Greek Civil War ends in Communist defeat.

A guerrilla group is a small, independent party which takes part in irregular fighting, typically against larger government forces.

Effect on the Truman Doctrine

The considerable resistance of the Communist Party of Greece and its military division the National Liberation Front to the Axis powers in WWII presented a threat to the Kingdom of Greece. Britain recognised this threat and continued to support Greece, but Britain's withdrawal in 1947 pushed the US to intervene.

Therefore, the British withdrawal from Greece can be considered a cause of the Truman Doctrine, contributing to the United States' growing fear of the spread of communism throughout Europe.

The Communist Party of Greece did not receive direct USSR support, which frustrated the Communists. However, the US recognised that if Greece was to become communist, it could cause a knock-on effect to other countries in the region.

One country of note was Greece's neighbour Turkey. If Greece was to succumb to communism, it was expected that Turkey would soon follow. Let's look at how the Turkish Straits Crisis also contributed to the establishment of the Truman Doctrine.

The Turkish Straits Crisis

Turkey remained mostly neutral during WWII, but this was due to the disputed control of the Turkish Straits. The USSR had no access to the Mediterranean without Turkish consent, which was supported by Britain. Stalin complained that Britain held proxy control over USSR naval movements, and proposed joint Soviet-Turkish control of the Straits.

The Turkish Straits connect the Black Sea to the Mediterranean. For the USSR, the Turkish Straits was the only strategic access to the Mediterranean. Let's look at a brief history of the Turkish Straits and the Crisis in 1946.

The Truman Doctrine map of the turkish straits StudySmarterThe Turkish Straits are the entry to the Black Sea from the Mediterranean and Soviet ships did not have freedom to move as they pleased. This caused tension between the USSR and Turkey. Source: Wikimedia Commons


1936The Montreux Convention formalises Turkish control of the Straits.
February 1945Invitations are sent to the inaugural meeting of the United Nations. Turkey accepts invitation, and officially declares war on the Axis powers, renouncing its prior neutrality.
July-August 1945The Potsdam Conference debates the Montreux Convention as USSR wants free use of the Turkish Straits. The matter is left unresolved between the USSR, the US, and Britain.
Early 1946The USSR increases its naval presence in the Black Sea, applying pressure on Turkey to accept Soviet co-control of Turkish Straits.
9 October 1946US and Britain reaffirm their support for Turkey, and Truman sends a US naval task force. Turkey specifically asks the US for aid in its resistance to Soviet forces and pressure.
26 October 1946USSR withdraws its naval presence and no longer threatens Turkish waters.
12 March 1947The Truman Doctrine is announced, sending $100 million to Turkey in economic aid and for continued democratic control of the Turkish Straits.

Effect on the Truman Doctrine

Since the Montreux Convention, the USSR had continually pressured Turkey to allow Soviet bases along the Turkish Straits. If the USSR had joint control of the Turkish Straits, they would have unrestricted access to the Mediterranean and a southern route to the Middle East.

Western powers were particularly concerned that this would allow the USSR to have further reach into both Europe and the Middle East. At the Potsdam Conference in 1945, Truman proposed that the Straits be internationalised and controlled by an international agreement. However, the USSR argued that if the Straits were internationalised, then so should the British-controlled Suez Canal and the US-controlled Panama Canal. Neither the UK nor the US wanted this and so declared that the Turkish Straits was a "domestic issue" to be resolved between Turkey and the USSR.

The increasing Soviet naval presence in the Black Sea threatened Turkey in 1946, and fears grew that would succumb to communism and Soviet influence. The capitalist West would lose access to the Straits despite Turkey's rejection of Soviet co-control. This threatened Western European supply lines across the Mediterranean. As Europe was already struggling economically after WWII, a Soviet-imposed reduction of supplies would worsen the economic crisis and create fertile ground for communist revolutions.

Turkey appealed for US aid in 1946. Therefore, the Turkish Straits Crisis can be seen as a cause for the Truman Doctrine as after Turkey's appeal, the US announced the Doctrine with its financial support to Turkey.

Announcement of Truman Doctrine Date

A key message within the speech on 12 March 1947 comes when Truman acknowledges the changes required for US foreign policy regarding Greece, Turkey, and any other nations under threat from communism. He says:

I believe it must be the policy of the United States to support free peoples who are resisting attempted subjugation by armed minorities or by outside pressures.

I believe that we must assist free peoples to work out their own destinies in their own way.

I believe that our help should be primarily through economic and financial aid which is essential to economic stability and orderly political processes.3

The Truman Doctrine President Harry Truman delivers his truman doctrine speech to congress 1947 StudySmarterThe Truman Doctrine changed US foreign policy to have a much more hands-on approach to containing communism and maintaining democratic freedoms. Source: Wikimedia Commons

Following Truman's speech, Secretary of State George C. Marshall and Ambassador George Kennan criticised Truman's "excess" rhetoric regarding the threat of Soviet expansion and communism. However, Truman argued that this new hardline foreign policy needed his over-explanation both to get the financial aid approved by Congress and to state the new direction regarding the future of Europe.

Truman thoroughly supported democracy and capitalism in his speech but makes no direct mention of Stalin or the Soviet Union. Instead, he refers to the "coercion" and the threat of "totalitarian regimes". Truman is hence careful to be pro-freedom but not expressly anti-Soviet, hence avoiding any possible direct declaration of war. However, the tougher approach to forces threatening democracy makes the Truman Doctrine one of the first steps in the Cold War between the US and USSR.

Consequences of the Truman Doctrine

The Truman Doctrine showed a fundamental change to US foreign policy regarding USSR expansion, protection against communism and protection of democracy and capitalism. The focus on US aid providing economic assistance paved the way for US foreign policy regarding nations which were threatened by communism.

Truman Doctrine and Marshall Plan

A key consequence of the Truman Doctrine was the introduction of the Marshall Plan in June 1947. The Marshall Plan indicated how the US would supply financial aid to European economies to support the post-WWII recovery. The Truman Doctrine combined with the Marshall Plan to demonstrate how the US was using financial aid to create political influence. This new approach to foreign policy contributed to the growing involvement of the US in international affairs and hence the Cold War with the USSR.

Cold War

The origins of the Cold War lie with the growing international tension between the US and USSR. Both the Truman Doctrine and the Marshall Plan indicated a change to US international relations against increasing Soviet aggression and expansion throughout Europe. The Truman Doctrine is a key cause, amongst others, of the Cold War in establishing the United States' stance against the spread of communism in Europe and the Middle East. This would culminate in the formation of the North Atlantic Treaty Organisation (NATO) in 1949, a military alliance designed to prevent a potential Soviet military expansion.

However, the Truman Doctrine still had many shortcomings and failures as a foreign policy. The focus on containing communism meant that the US was not giving proper attention to the spread of other ideologies, particularly nationalism, in nations like Vietnam and Cuba. Whilst the Truman Doctrine had proven successful in Greece and Turkey, this did not mean that every fight would be so easily won. Instead, the US saw massive failures in the aforementioned Vietnamese and Cuban conflicts as they simply hadn't thought of the negative reaction to American political interference.

Truman Doctrine - Key Takeaways

  • The Truman Doctrine was announced on 12 March 1947 and detailed the United States' new hardline approach to foreign policy. Truman promised financial aid to Greece and Turkey, whilst also committing the US to the fight against totalitarian regimes.
  • After WWII, the USSR continued to occupy Eastern European countries and Kennan's 'Long Telegram' detailed the threat of Soviet expansionism throughout Europe. This influenced US foreign policy, which was further developed by the events in Greece and Turkey.
  • The Greek Civil War was fought in two stages, between 1944-45 and 1946-49. Both stages were fought between the Kingdom of Greece and the Communist Party of Greece. Britain supported the Monarchists in the first stage but withdrew in 1947. The US supplied Greece with $300 million in its fight against communism because of fears that the Communist Party of Greece would come under Soviet influence.
  • The Turkish Straits Crisis officially began when the USSR intimidated Turkey through an increased naval presence in the Black Sea in 1946. The USSR wanted co-control of the Straits with Turkey so that it could freely access the Mediterranean. After Turkey explicitly asked the US for support, the Truman Doctrine promised $100 million and sent a US naval task force.
  • The Truman Doctrine led to the Marshall Plan for the US to provide foreign aid to countries economically recovering from WWII in hopes of containing the spread of communism. By committing US foreign policy to economic aid with political influence, the Truman Doctrine is a key starting point for the Cold War.

1 'George Kennan's Long Telegram', February 22, 1946, in Foreign Relations of the United States, 1946, Volume VI, Eastern Europe; The Soviet Union, (Washington, DC, 1969), pp 696-709.

2 Ibid.

3 'President Harry S. Truman's Address before a Joint Session of Congress', March 12 1947, Congressional Record, 93 (12 March 1947), p. 1999.

Frequently Asked Questions about Truman Doctrine

The Truman Doctrine was a speech given by US President Harry Truman on 12th March 1947 declaring the change in US foreign policy. The US committed to financially supporting Greece and Turkey for $400 million in order to suppress communism and support democratic governments. The Doctrine also stated that the US would be involved in international affairs and protect nations from "coercion" by "totalitarian governments" heavily alluding to the USSR's policies of communist expansion.

US President Harry Truman announced the Truman Doctrine on the 12th March 1947.

The Truman Doctrine stated US foreign policy regarding the spread of communism across Europe. The Doctrine advocated the "freedoms" under democracy and stated that the US would support any nation threatened by the "coercion" of "totalitarian regimes". This opposed Stalin's plans of Soviet expansion, and hence provided a clear opposition to communism. This then spurred the ideological conflict of the Cold War in the decades to come.

The Truman Doctrine promised to "support free peoples who are resisting attempted subjugation by armed minorities or by outside pressures". This promised to protect "free" democratic nations from the spread of totalitarian regimes, alluding to the communism from the USSR.

Test your knowledge with multiple choice flashcards

Why was the Truman Doctrine introduced?

Which international organisation was created as an indirect result of the Truman Doctrine?

What did Truman do in order to ensure Congress would pass the Truman Doctrine?


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