Canada says it considered risk of US attack: How their militaries compare

With Canadian Prime Minister Mark Carney saying his government has considered the possibility of US military action against Canada, an extraordinary scenario has entered the public debate between two countries that have historically maintained one of the world’s closest defence partnerships.The United States and Canada share an approximately 8,900-kilometre border and have worked together on North American defence for decades.Their militaries operate together through the North American Aerospace Defense Command (NORAD), the binational command responsible for monitoring and defending North American airspace and maritime approaches.Carney, however, described possible US military action as an “extreme tail risk” that his government had a responsibility to examine and prepare for. His comments came amid heightened tensions between Washington and Ottawa, including disputes over trade and President Donald Trump's repeated remarks about Canada becoming the “51st state”.The scenario remains remote, with Carney stressing that it is not his government's “base case”.