Before that whole treason thing sullied his historical legacy, Benedict Arnold led an invasion force into Canada during the American Revolution. He failed miserably.
In 1839, a cow (American), a pig (Canadian) and a handful of militiamen (American) were injured in the Aroostook War, a short and unofficial conflict between Maine and Canada over a border dispute.
Invading Canada, it seems, is as American as apple pie. The only problem is that we suck at it. Well, traitors and lumberjacks do, anyway. If you want a job done right, you have to go to the big boys, but surely the federal government wouldn't ever dream of invading friendly, free-trading Canada. Would they?
Turns out, the United States government did have a plan to invade Canada. "Joint Army and Navy Basic War Plan - Red" is a 94-page, step-by-step plan to invade, capture and annex the land of maple syrup.
The plan was one of a handful of color-coded war plans developed as strategies for various hypothetical war scenarios by a War Department with too much time on its hands in the 1920s and 30s. In War Plan Red, the government imagined a conflict between the United States and England over international trade, with Canada, still a semi-independent British dominion at the time, as the launching point for English ground attacks.
Plan Red outlines a series of possible campaigns aimed at capturing key ports, cities and railroad lines before British reinforcements could arrive, preventing them from using Canadian resources and infrastructure to their advantage.
While a joint Army-Navy overseas force captured the port city of Halifax, cutting Canada off from the Atlantic, the U.S. Army would attack on three fronts, advancing from North Dakota, Vermont, and the upper Midwest to capture Winnipeg, Montreal and the nickel mines of Ontario, respectively. American forces were also supposed to capture British colonies in the Caribbean to defend the country from an attack from the south.
The Canadian Response
Those wily Canucks were one step ahead of us, though. Colonel James "Buster" Sutherland Brown developed a plan called Defence Scheme No. 1 a full nine years before War Plan Red was drawn up. Buster's plan called for Canadian troops to attack and occupy Seattle, Portland, Minneapolis and St. Paul and Albany in order to divert American forces to the flanks long enough for English reinforcements to arrive. This isn't a bad plan considering the Canadian department responsible for war planning had an annual budget of $1,200, and Buster did most of his reconnaissance by driving across the border, taking photos and grabbing free maps at gas stations.
The hypothetical war, of course, never happened. Canada and the United States became allies during World War II, and partners in NATO and NAFTA. Today, the two countries share the world's longest demilitarized border, which has the world's largest number of legal crossings. War Plan Red and its color-coded siblings were withdrawn in 1939 and declassified in 1974. They now reside in the National Archives, where foreign spies can photocopy them for 15 cents a page (War Plan Red is online, too). And everyone lived happily ever after.
And those other color plans? Well, here are my favorites:
War Plan Citron: an invasion of Brazil
War Plan Emerald: intervention in Ireland in conjunction with War Plan Red
War Plan Green: war with Mexico in order to establish a pro-American government
War Plan Indigo: an invasion of Iceland (in 1941, parts of the plan were actually used during Battle of the Atlantic when the US relieved British occupation forces)
War Plan Lemon: an invasion of Portugal
War Plan White: plan for dealing with civil disturbances cause by Communist insurgents