Canada must prepare for an isolationist and unpredictable neighbor to the South should a MAGA leader gain the White House in 2025. The American-led global order has been increasingly challenged by Chinese assertiveness and Russian revanchism. As we enter this new era of great-power competition, Canadians tend to assume that the United States will continue to provide global leadership for the West. Canada Alone sketches the more dystopian future that is likely to result if the illiberal, anti-democratic, and authoritarian Make America Great Again movement regains power. Under the twin stresses of a reinvigorated America First policy and the purposeful abandonment of American global leadership, the West will likely fracture, leaving Canadians all alone with an increasingly dysfunctional United States. Canada Alone outlines what Canadians will need to navigate this deeply unfamiliar post-American world.