"Relations between the United States and Canada, though generally close, have undergone changes in tenor over the past three decades. During the 1980s, the two countries generally enjoyed very good relations. The early 1990s brought new governments to Ottawa and Washington, and although Canada's Liberal Party emphasized its determination to act independently of the United States when necessary, relations continued to be cordial. In early 2006, a minority Conservative government assumed power in Ottawa. It was regarded as being more philosophically in tune with the George W. Bush Administration than the Liberals were; some observers believe that this compatibility helped facilitate bilateral cooperation. The election of President Obama November 2008 signaled a new chapter in U.S.-Canada relations; unlike President Bush, Obama is quite popular in Canada. The two North American countries continue to cooperate widely in international security and political issues, both bilaterally and through numerous international organizations. Canada's foreign and defense policies are usually in harmony with those of the United States. Areas of contention have been relatively few, but sometimes sharp, as was the case in policy toward Iraq. Since September 11, the United States and Canada have cooperated extensively on efforts to strengthen border security and to combat terrorism, particularly in Afghanistan."
CRS Report for Congress, 96-397