<P> During the Suez Crisis of 1956, the idea promoted by Canada in 1945 of a United Nations military force returned to the fore . The conflict involving Britain, France, Israel and Egypt quickly developed into a potential flashpoint between the emerging' superpowers' of the United States and the Soviet Union as the Soviets made intimations that they would militarily support Egypt's cause . The Soviets went as far as to say they would be willing to use "all types of modern weapons of destruction" on London and Paris--an overt threat of nuclear attack . Canadian diplomat Lester B. Pearson re-introduced then Prime Minister Louis St. Laurent's UN military force concept in the form of an' Emergency Force' that would intercede and divide the combatants, and form a buffer zone or' human shield' between the opposing forces . Pearson's United Nations Emergency Force (UNEF) - the first peacekeeping force, was deployed to separate the combatants and a cease - fire and resolution was drawn up to end the hostilities . </P> <P> To defend North America against a possible enemy attack, Canada and the United States began to work very closely together in the 1950s . The North American Aerospace Defense Command (NORAD) created a joint air - defense system . In northern Canada, the Distant Early Warning Line (Dew Line) was established to give warning of Soviet bombers heading over the north pole . Great debate broke out while John Diefenbaker was Prime Minister as to whether Canada should accept U.S. nuclear weapons on its territory . Diefenbaker had already agreed to buy the BOMARC missile system from the Americans, which would be not as effective without nuclear warheads, but balked at permitting the weapons into Canada . </P> <P> Canada also maintained diplomatic and economic ties with Cuba following the Cuban Revolution . Prior to the Cuban Missile Crisis, the insistence on a much more placated policy towards the Cuban government had been a source of contention between the United States and Canada . Prime Minister Diefenbaker firmly stood by his policy decision, insisting that this was the result of the rights of states to establish their own forms of government, rejection of current US interpretation of the Monroe Doctrine as well as Canada's right to establish its own foreign policy . Concern in the Canadian government was focused primarily on nuclear weapons, many politicians in the opposition and in power believed that as long as the US president retained absolute control of the nuclear weapons, Canadian forces could be ordered to undertake nuclear missions for the US without Canadian consent . During the Cuban Missile Crisis, Canada was expected to fall in line with American foreign policy, in that Canada's military forces were expected to go on immediate war alert status . Diefenbaker however, refused to do so emphasizing the need for United Nations intervention . It would only be after a tense phone call between President John F. Kennedy and Diefenbaker that Canada's armed forces would begin preparations for "immediate enemy attack". Although the crisis would eventually be solved by diplomatic talks between Nikita Khrushchev and Kennedy, nothing would loom larger over the Canadian state in the months following the crisis than the governing party's disarray on the question of nuclear arms . </P> <P> In the 1963 Canadian election, Diefenbaker was replaced by the famed diplomat Lester B. Pearson, who accepted the warheads . Further tensions developed when Pearson criticized the American role in the Vietnam War in a speech he gave at Temple University in Philadelphia, Pennsylvania . See also Canada and the Vietnam War . </P>

What did canada do in the cuban missile crisis
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