According to Hector Mackenzie, the myth of a glorious postwar era in Canada's international relations is common in memoirs and biographies of Canadian diplomats, journalism and popular commentary. It sometimes appears in scholarly studies. This story is used as evidence of Canada's exceptionalism, its special world mission and its supposed deeply felt internationalism. It is easy to take this myth as a standard against which recent history is judged. Mackenzie argues the myth is deeply mistaken especially regarding Canadian motives and achievements in world affairs during 1939 to 1957. Diplomats reminiscing about the postwar era stress the outsized role of Lester B. Pearson; they fondly call the 1940s and 1950s a "golden era" of Canadian foreign policy. It is matched against the isolationism of the 1930s, which James Eayrs called a low, dishonest decade." However, the Golden Era tag has been challenged as a romantic exaggeration. Prime Minister William Lyon Mackenzie King, working closely with his Foreign Minister Louis St. Laurent, handled foreign relations 1945–48 in cautious fashion. Canada lent and donated over $2 billion to Britain to help it rebuild (by purchasing Canadian exports). It was elected to the UN Security Council. It helped design NATO. However, Mackenzie King rejected free trade with the United States, and decided not to play a role in the Berlin airlift. Canada had been actively involved in the League of Nations, primarily because it could act separately from Britain. It played a modest role in the postwar formation of the United Nations, as well as the International Monetary Fund. It played a somewhat larger role in 1947 in designing the General Agreement on Tariffs and Trade. Ties with Great Britain gradually weakened, especially in 1956 when Canada refused to support the British and French invasion of Egypt in order to seize the Suez Canal. Liberal Lester B. Pearson as External Affairs Minister (foreign minister) won the Nobel Peace Prize for organizing the United Nations Emergency Force in 1956 to resolve the Suez Canal Crisis.