During the interwar period, the United States secretly planned a full-scale invasion of Canada.

History · Published 29 September 2026 Swipe more like this →

In short: This documentary explores War Plan Red, the American military strategy developed after World War I to wage war against the British Empire. It details the planned conquest of Canada and the corresponding defensive schemes drafted by Canadian officials.

As tensions between the United States and the British Empire rose following World War I, American military planners created a series of color-coded strategies. War Plan Red specifically focused on a potential conflict with Britain, centering on an invasion of Canada. The strategy included targeted strikes on major cities such as Halifax, Montreal, and Vancouver, and even involved intelligence gathering through spy flights conducted by Charles Lindbergh.

In response to these threats, Canada developed Defense Scheme No. 1, which proposed preemptive surprise attacks on American cities. The documentary examines the military forces involved, including estimates for British and Canadian troop mobilization, and explains how these ambitious, chilling plans were ultimately abandoned before the outbreak of World War II.

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