Cold War alliances

cold war alliances

NATO delegates discuss defences in south-east Asia

Cold War alliances like NATO and the Warsaw Pact both reflected and intensified the divisions between democratic and socialist nations. In the years following World War II, European nations took steps to align with others to protect themselves from future aggression. Some expected this might come from resurgent Nazism, either as a secret counter-attack or as guerrilla resistance to Allied occupation. Others believed the menace would come from Soviet aggression. In March 1947, Britain and France signed the Treaty of Dunkirk, a bipartisan military alliance. In March 1948 they extended this alliance by signing the Treaty of Brussels, a new agreement that included Belgium, Luxembourg and the Netherlands. Though the Treaty of Brussels did not specifically mention the Soviet Union, it was predicated on resisting communism and communist expansion. The treaty’s preamble made its political aims quite clear: to “fortify and preserve the principles of democracy, personal freedom and political liberty, the constitutional traditions and the rule of law” that were the “common heritage” of the five signatory nations.

cold war alliances

Harry S. Truman and other leaders sign the NATO treaty in 1949

Just weeks after the signing of the Treaty of Brussels, Soviet forces initiated their blockade of Berlin. Interpreting this blockade as an act of aggression, the Brussels signatories formed their own military agency: the Western Union Defence Organisation. But despite their alliance, these European states still harboured concerns about their incapacity to respond to Soviet military aggression. Like most other European nations, the Brussels signatories had demobilised and reduced their military forces at the end of World War II. Their combined forces were incapable of serving as a deterrent to Soviet aggression, nor could they respond adequately in the event of war with the USSR. These nations began lobbying Washington, urging it to form a trans-Atlantic military alliance. Following lengthy negotiations, the North Atlantic Treaty was signed in Washington in April 1949.

NATO’s early years

“NATO began as a military alliance, but it was never just a military alliance of the traditional sort. As US secretary Dean Acheson said, ‘the North Atlantic Treaty is far more than a defensive arrangement. It is an affirmation of the moral and spiritual values we hold in common.’ Stanley Sloan affirms this: ‘What made NATO different from previous military alliances was that the Treaty’s preamble clearly articulated allied support for democracy, individual liberty and the rule of law.'”
Michael J. Williams, historian
cold war alliances

The emblems of NATO, then and now

The members of the North Atlantic Treaty Organisation (NATO) included the US, all five Brussels treaty nations, Canada, Denmark, Iceland, Italy, Norway and Portugal. Several countries were invited to join NATO but refused, including Finland, Ireland, Sweden and the ever-neutral Switzerland. Three more countries – Greece, Turkey and West Germany – were all admitted to NATO during the 1950s. France was a foundation member but its military commitment to NATO was gradually reduced between 1959 and 1966, as Paris preferred to formulate its own defence strategies. Under the terms of the North Atlantic Treaty, an “armed attack” against any of the signatory nations was to be “considered an attack against them all”, requiring members to take “such action as [they deem] necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area.”

In its first year, NATO was little more than a loose association of nations, who exchanged military expertise, advice and hardware. The onset of the Korean War in 1950 hardened the alliance, prompting NATO to expand and develop new command structures. In 1952 the office of NATO secretary-general was created, and NATO’s headquarters were moved from small offices in London to a dedicated complex in Paris. Exercise Mainbrace, the first NATO ‘war games’, were conducted in northern European waters by nine member navies. NATO commanders also drew up war plans and strategies to deal with various Soviet attack or invasion scenarios. In 1954, a year after the death of Stalin, NATO was tested by a request for membership from the Soviet Union. The proposal was rejected by NATO member-states, who said ‘the unrealistic nature of the proposal does not warrant discussion’. West Germany, in contrast, was admitted to membership the following year.

The Soviets respond

cold war alliances

The Warsaw Pact conference of Soviet bloc nations, 1955

Their rejection from NATO prompted Soviet leaders to form their own rival alliance. In May 1955, Moscow convened a conference of communist delegates in the Polish capital Warsaw. They drafted and signed the Treaty of Friendship, Cooperation and Mutual Assistance, more commonly known as the Warsaw Pact. The pact’s eight member-nations were the USSR, Poland, East Germany, Albania (until 1968), Bulgaria, Czechoslovakia, Hungary and Romania. In a similar fashion to NATO, the Warsaw Pact had civil, political and military committees and its own headquarters, located in Warsaw. Its planning, decision-making and military command were dominated by the Soviet Union. Warsaw Pact bodies were led by Soviet politicians, diplomats or bureaucrats; the supreme commander of Warsaw Pact forces, for instance, was also the Soviet deputy defence minister. This contrasted with US involvement in NATO: America was undoubtedly the major military partner but did not command or control the alliance.

cold war alliances

NATO troops participate in a simulated landing in Turkey in 1957

The formation of the Warsaw Pact sparked a revision of NATO and an escalation of its activities. NATO members recruited West Germany, believing its population would be crucial in the event of a war with the Soviet bloc. NATO exercises also increased in size and frequency. In September 1957, more than 300 NATO ships and a quarter-million men took part in joint exercises in the North Atlantic Sea and Mediterranean. The first of these was Operation Strikeback, a mock battle against an enemy submarine fleet. NATO forces also participated in Operation Deep Water, responding to a simulated Soviet invasion of the Dardenelles (Turkey). In central Europe, Operation Counter Punch tested NATO’s air defence capabilities.


A diagram showing the deployment of US nuclear weapons in Europe

A diagram showing the deployment of US nuclear weapons in Europe

One of the most controversial aspects of NATO was its nuclear-sharing arrangements. Under this scheme, American nuclear weapons, bombers and missile systems were provided to non-nuclear NATO states. Access codes for these weapons remained with the US military – but in the event of a war with the Soviet bloc, they would be provided to host states. Nuclear sharing began in 1954 with the deployment of US nuclear weapons in Britain. Other European countries to be provided with these weapons included West Germany, Italy, Greece, Belgium and Turkey. In contrast to NATO, the Warsaw Pact resisted any form of nuclear sharing. Soviet nuclear weapons were certainly deployed in satellite states, but their use was controlled entirely by Moscow.

NATO and the Warsaw Pact existed alongside many other Cold War treaties and alliances. In September 1951, the US, Australia and New Zealand signed the ANZUS treaty, a tripartite military alliance. (The US-NZ arm of the alliance broke down in 1985, following disputes over American nuclear ships docking in New Zealand ports.) Washington signed a Mutual Defence Treaty with the Republic of China (Taiwan) in 1954, providing the latter with American support in the event of an attack or invasion by communist China. A September 1954 pact formed the South-East Asia Treaty Organisation (SEATO), an anti-communist alliance – in effect, an Asian-Pacific version of NATO. There were a myriad of other smaller treaties and agreements signed by individual nations, which reflected both their domestic and regional interests as well as Cold War factors.



1. The Cold War world was shaped and divided by political and military alliances, like NATO and the Warsaw Pact.
2. NATO was formed in 1949, an expansion of the Treaty of Brussels in response to Soviet expansion.
3. The Soviet bloc responded by forming its own military alliance, the Warsaw Pact, signed in 1955.
4. This led to an increase in NATO planning and operations, including military exercises and nuclear-sharing.
5. There were bilateral and multilateral Cold War treaties signed in other parts of the world too, such as the SEATO and ANZUS treaties in the Asia-Pacific.

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