Canada and the Cuban Missile Crisis

The Cuban Missile Crisis lasted from 16 to 28 October 1962. The Soviet Union stationed nuclear missiles in Cuba, which posed a threat to the United States and Canada. It brought the world to the edge of nuclear war. Canadian armed forces were placed on heightened alert. Prime Minister John Diefenbaker’s hesitant response to the crisis soured already tense relations between Canada and the US and led to the downfall of his government in 1963.   

Cuban Missile Crisis

An S-75 Dvina surface-to-air missile (SAM) in front of the Military-Historical Museum of Artillery, Engineer and Signal Corps in St. Petersburg, Russia.

Missiles Discovered

The Cuban Missile Crisis took place at the height of the Cold War. On 14 October 1962, an American spy plane took photographs of Soviet ballistic missiles being installed in Cuba. Equipped with nuclear warheads, the missiles were capable of hitting targets in the United States or Canada.

US President John F. Kennedy was informed of the situation on 16 October. He and his advisors spent a week secretly discussing what to do. Kennedy rejected calls from his military to launch air strikes against the missile sites. Instead, he mounted an immediate naval blockade of Cuba. He announced the crisis, and the blockade, in a televised address to the American public on 22 October. He threatened the Soviet Union with further action if the missile sites were not dismantled.

Canada Hesitates

Like other NATO leaders, Prime Minister John Diefenbaker was informed by Kennedy of the US plan shortly before the televised broadcast. The two leaders did not get along well at the best of times. On the phone with Kennedy, Diefenbaker was skeptical about the Soviet Union’s intentions. He asked to see further proof of what was taking place on the ground in Cuba. Diefenbaker urged Kennedy to send a team of United Nations inspectors to Cuba to verify what the Soviets were doing there.

The main issue for the Canadian government was whether to comply with an American request to move Canadian forces to a higher alert status known as “DEFCON-3.” Diefenbaker, who disliked Kennedy, was reluctant. He was angry that the US hadn’t consulted Canada earlier in the crisis. He and Canada’s Foreign Minister, Secretary of State for External Affairs Howard Green, were also wary of falling too quickly into line with American demands. They were also concerned that placing Canada’s military on alert might provoke the Soviet Union.

Cuban Missile Crisis

Aerial view showing missile launch site 3 in Cuba, October 1962.


In spite of these concerns and delays, National Defence Minister Douglas Harkness asked Canadian units to raise their alert level to “DEFCON-3.” However, formal permission was delayed while Cabinet debated the matter for the next two days. Harkness argued that the nature of the crisis, combined with international treaties, made the alert necessary (Canada was a member, along with the US, of both NATO and NORAD).

About half of Canada’s ministers remained undecided on the issue. But as Soviet ships approached the quarantine zone later in the week, other NATO members announced their support for the blockade. Harkness’s position gained support. On 24 October, the Diefenbaker government authorized the “DEFCON-3” alert. Canadian ships and aircraft also participated in patrols at this time to locate Soviet submarines in the North Atlantic.

Canada’s hesitant response reflected the government’s desire to preserve the independence of its foreign policy. It also wanted to maintain a balanced posture in crisis conditions. The delay, however, was widely criticized in Canada. It led to a growing perception that the Diefenbaker government was indecisive.

Canada’s hesitancy worsened already tense relations with the Kennedy administration. It also fuelled controversy and confusion in Canada over the country’s policy on nuclear weapons. This had first surfaced in the 1960 debate on Bomarc missiles.

John Diefenbaker
John Diefenbaker, prime minister of Canada from 1957-1963.


The Cuban Missile Crisis lasted for 13 tense days. The world’s two atomic superpowers came closer than ever to nuclear war. The stand-off ended on 28 October with the help of United Nations diplomats. Soviet Premier Nikita Khrushchev agreed to dismantle and remove the Soviet missiles, in return for Kennedy’s promise not to invade Cuba.

Impact on Canada

Diefenbaker had won the 1958 election with the biggest landslide in Canadian history. But his hesitant response to the Cuban missile crisis led to the downfall of his regime. In the wake of the crisis, the US accused the Diefenbaker government of lying and avoiding its military duties. Harkness resigned as minister of defence. Diefenbaker’s Progressive Conservatives lost to Lester B. Pearson and the Liberal Party in the election on 5 February 1963.

Further Reading

  • Robert F. Kennedy, Thirteen Days: A Memoir of The Cuban Missile Crisis (1968).
  • Sean M. Maloney, Learning to Love the Bomb: Canada's Nuclear Weapons During the Cold War (2007).
  • Peter T. Haydon, The 1962 Cuban Missile Crisis: Canadian Involvement Reconsidered (1993).
  • Michael Dobbs, One Minute to Midnight: Kennedy, Khrushchev, and Castro on the Brink of Nuclear War (2008). 
  • Sheldon Stern, The Week the World Stood Still: Inside the Secret Cuban Missile Crisis (2005).
  • Patrick Lennox, At Home and Abroad: The Canada-US Relationship and Canada's Place in the World (2009).