In the aftermath of September 11th many commentators expressed renewed concerns that the United States' reliance on the Middle East as a petroleum source made it politically and economically dependent upon an unstable region. Most of these observers also voiced a sense of pessimism about the United States' ability to change this situation. Yet in fact the United States' energy position is now stronger than it appears, and there is reason to believe that it will improve in the future, because of the growing importance of Canada as a source of petroleum. According to Canada's National Energy Board, Canada has the world's largest deposit of oil sands, which may equal or exceed the proven petroleum reserves of Saudi Arabia. Canada is already the largest exporter of petroleum to the United States, and its production will likely triple this decade. This will place renewed pressure on OPEC, weaken the political influence of Saudi Arabia and greatly strengthen the United States' energy position. This paper will describe the rapid changes in Canada's petroleum industry, and how this may affect the United States from a security perspective.