America Once Had a Detailed Plan to Invade Canada: Poison Gas on Halifax, a Drive on Winnipeg, and No Plans to Give Anything Back

America Once Had a Detailed Plan to Invade Canada: Poison Gas on Halifax, a Drive on Winnipeg, and No Plans to Give Anything Back

For most of a century the US and Canada have shared the longest undefended border on Earth. For part of that century, both capitals kept invasion plans for each other in locked drawers. War Plan Red, approved at cabinet level in 1930 and classified until 1974, mapped an American conquest of Canada that opened with a gas attack on Halifax and ended with no return of captured territory. Canada's Defence Scheme No. 1, drafted nine years earlier, se…