The Curious Cases of Anglo-Canadian Military Plans to Invade the United States: WWI, WWII, and the 1920s

Throughout history, the relationship between the United States and Canada has been a complex one, with periods of cooperation and periods of tension. Among the more intriguing episodes in this history are the various military plans developed by Anglo-Canadian forces to invade the United States, particularly during the two World Wars and the inter-war years. In this article, we will explore these fascinating historical curiosities.

The Lack of Plan in WWI and WWII

When examining the First and Second World Wars, it becomes clear that Anglo-Canadian forces had no real plans to invade the United States. During World War I, the USA was initially a friendly neutral to the British Empire until it joined the war in 1917 on the side of the Allies, declared by President Woodrow Wilson. Canada, as a British colony at the time, had no authority to plan such an invasion. When World War II broke out, although Canada had effectively become an independent state by 1939, it joined the UK in its war against Nazi Germany on September 10, 1939. The United States became a friendly neutral until December 11, 1941, when it declared war on Japan, a country with whom it was not at war until then. The notion of an Anglo-Canadian invasion of the United States was therefore non-existent in both World Wars, as both countries remained on good terms.

Furthermore, Canada's military presence was overseas during both wars, with no capacity to attack a much larger and more populous enemy well-entrenched at home. Historically, it would have been absurd for Canada to consider such a move given the overwhelming military advantage the USA would have had on its soil.

The War of 1812: An Early Mishap

During the War of 1812, there were indeed cases of invasion, but not as part of a coordinated plan by Anglo-Canadian forces. The U.S. invasion of Canada during this war accorded with the idea of humanitarian liberation, despite the later burning of the Government buildings in York, Ontario (now Toronto). The Americans also burned Washington, which was a direct retaliation for similar actions by the British. This was not the history taught in most U.S. schools.

The 1920s: A Speculative Anglo-Canadian Invasion Plan

However, during the inter-war period, a more speculative plan emerged. In 1921, Lieutenant Colonel James Sutherland "Buster" Brown, head of Military Operations and Intelligence, developed a plan to preempt a potential American mobilization to attack Canada. According to his plan, Canadian troops would invade the United States, with four main segments:

Troops from British Columbia would seize Seattle, Spokane, and Portland. Troops from Prairie Command would capture Great Falls, Montana, and Fargo, North Dakota, before advancing towards Minneapolis. Troops from Quebec would launch a surprise attack on Albany, New York. Troops from Maritime Command would seize Maine.

As American resistance increased, Canadian troops would withdraw, destroying bridges, road junctions, and rail lines as they went. While this plan seems incredible today, during the 1920s and 1930s, the U.S. was indeed developing its own plan against the UK, known as War Plan Red, and a component of this war plan, Plan Crimson, was the invasion of Canada. In this plan, the U.S. planned to seize New Brunswick and Nova Scotia, particularly the naval base at Halifax, with a ground and sea assault using poison gas.

The U.S. army also planned to capture Quebec City and Montreal, thus blocking movements between eastern and central Canada. Attacks from Niagara Falls, Detroit, and Sault Ste. Marie would target Toronto, preventing the area from being used for air attacks. Another thrust from Grand Forks would take Winnipeg, the nexus of the Canadian rail system, while an amphibious assault would target the naval base at Esquimalt/Victoria on Vancouver Island. Additionally, the Port of Prince Rupert would be blockaded.

The biggest problem that neither Brown nor the Americans anticipated was the British reaction. The British government believed that if there was a war with the United States, they could transport troops to Canada if requested, but did not believe the loss of Canada would be fatal to the British Empire. They also did not anticipate that the U.S. would launch attacks on British trade in the Pacific and the Indian Ocean. While the British did develop a basic plan involving facing the American fleet in the Western Hemisphere and taking Manila, this was not a fully developed war plan.

In conclusion, while there were no real plans to invade the United States during World War I and World War II, Anglo-Canadian forces did consider potential scenarios in the inter-war period, driven more by speculation than actual military strategy. Such plans highlight the complexities of international relations and the fascination of historical curiosities.