On 24 February 2005, Foreign Affairs MinisterPierre Pettigrew announced Canada would not be joining the United States' missile defense program. In Canada, there was some level of debate over participation in the U.S. missile defense program. Many Canadians felt that the program would do great damage to international peace and security by creating a new arms race among the great powers. This viewpoint was shared by many who feared the increasingly aggressive U.S. foreign policy under George W. Bush, and who resented the suggestion that Canada may not have an independent foreign policy. Many also opposed the system because of the doubts of some physicists about the effectiveness of the system. In his first visit to Canada shortly after winning his second U.S. election, President Bush surprised Prime MinisterPaul Martin by making a speech calling on Canada to join the program and invoking the memory of former Prime Minister W.L. Mackenzie King's response to Nazi Germany. The Canadian Department of National Defence had mixed feelings about participation in the program. It wished to retain the current level of Canadian involvement in North Americanair defence through NORAD, but was reluctant to see scarce military funds spent on a single large research and development project of dubious practical value. There was a widespread feeling in Canada that failure to participate in the program would mean being shut out of American defense planning, something that would not be in the Canadian national interest. Others feared that rejection of the plan would lead to a cooling of Canada-U.S. relations, and might even lead to reprisals. Thus, while some Canadians were unsure about the viability of the system, many supported joining for diplomatic reasons. Opponents of involvement replied that Canada must have the courage to oppose the system on moral grounds, even if this decision proved to have negative consequences. They contended that it was important for Canada to reestablish its voice in the international arena by pushing for global disarmament and a revitalization of the United Nations.