The War of 1812 opened on a high note for the United States. With cries of “On to Canada,” America’s war hawks dreamed of empire. Even Thomas Jefferson had boasted that taking the British colony would be “a mere matter of marching.” President James Madison appointed a 59-year-old Revolutionary war hero, William Hull, the governor of the Michigan territory, to be commander of the Army leaving Fort Detroit for the territory north of Lake Ontario known as Upper Canada.

In July, Hull began his invasion at the head of 2,500 troops, telling the Canadians if they didn’t enjoy becoming an…