The expansion of the war in 1942 pulled Canada’s small ship navy in several directions simultaneously, stretching it thin and leading—ultimately—to the greatest crisis in Canadian naval history. The navy’s senior officers were sharply criticized for the way in which they handled these challenges and the Chief of Naval Staff, Admiral Percy Nelles, was dismissed in January 1944. It is hard to know how they could have done better with what they had to work with. As always in the struggle against the U-boats, the enemy had the initiative and Allied resources were limited. The Royal Canadian Navy’s response to sudden expansion of the U-boat war in 1942 was primarily to extend the system of escorted convoys. It was a highly successful strategy, even if the navy proved incapable of winnin...