NATO (North Atlantic Treaty Organization), established in 1949, was Canada's first peacetime military alliance, placing the nation in a defensive military arrangement with the US, Britain and the nations of western Europe. In 1947 there was much concern in Ottawa as the Soviet Union created a buffer zone in eastern Europe between itself and West Germany. The USSR was apparently pursuing a policy of aggressive military expansion at home and subversion abroad, and there was real fear that France or Italy might become communist (see COLD WAR).

The problem was complicated by what Ottawa saw as a resurgent isolationism in the US, an unwillingness by Congress to pick up the international burdens that France and Britain, both weakened by WWII, could no longer bear. The answer seemed to lie in an arrangement that would link the democracies on both sides of the Atlantic into a defensive alliance, thus securing western Europe from attack while involving the US firmly in world affairs. An extra advantage for Ottawa was that such an arrangement would bind together all of Canada's trading partners, and it thus suggested potential economic benefits.

The initial public expression of this thinking was that of Escott REID, Department of External Affairs (now FOREIGN AFFAIRS AND INTERNATIONAL TRADE), at the COUCHICHING CONFERENCE on 13 August 1947. Other Canadians, including Reid's minister, Louis ST. LAURENT, picked up the idea, and it was soon being discussed in Washington and London. Secret talks between the British, Americans and Canadians followed, and these led to formal negotiations for a broader alliance in late 1948.

Canada's representative was Hume WRONG, ambassador to the US and a hardheaded realist. Wrong believed any treaty should be for defence alone, a view popular among the other participants. But Ottawa had grander visions, and L.B. PEARSON and Reid pressed him to argue for the inclusion of a clause calling for the elimination of economic conflicts among the parties. Despite misgivings, Wrong secured the inclusion of Article II, the "Canadian article." Regrettably, little came of it.

The treaty was signed 4 April 1949, but it was largely a paper alliance until the KOREAN WAR. That led the NATO states to build up their forces, and for Canada this had major consequences: a huge budget increase and the first stationing of troops abroad in peacetime. The Canadian contribution was small, but its quality was widely considered to be second to none. Nonetheless, high costs and the nuclear arms given the forces in 1963 worried critics.

After a major review of foreign policy, the Trudeau government decided in 1969 to cut the Canadian contribution drastically, reducing the army and air elements. Canadian commitment of arms and men to the alliance remained substantially lower than other NATO partners wished.

As the Cold War ended in the early 1990s, NATO underwent a transformation. The collective defence organization assumed a broader range of responsibilities to become a security and co-operation agency at the service of peace. Canada was a strong supporter of NATO's reform and expansion, asserting that NATO had become the embodiment of the ideals with which it had been established.

The Alliance's priorities have evolved with global developments. The day after the September 11, 2001 terrorist attack on the World Trade Center in New York, NATO invoked Article 5 of its Charter for the first time in its history. Article 5 is known as the collective defence article. Under the Article, if a NATO ally is the victim of an armed attack, every other member will consider the action as having been committed against all members and will take the necessary actions to assist the attacked ally.

At the NATO Prague Summit, November 21-22, 2002, members agreed to make further changes to ensure that the Alliance remains a central mechanism for meeting members' security needs. This commitment involves inviting new members to join the organization, enhancing relationships with NATO's partner countries and giving the Alliance new capabilities.

Member countries of the NATO Alliance are: Albania; Belgium; Bulgaria; Canada; Croatia; Czech Republic; Denmark; Estonia; France; Germany; Greece; Hungary; Iceland; Italy; Latvia; Lithuania; Luxembourg; Netherlands; Norway; Poland; Portugal; Romania; Slovakia; Slovenia; Spain; Turkey; United Kingdom; United States.