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The plan had detractors, who saw it as unrealistic, but it also had supporters who believed that it could conceivably have worked. When American resistance grew, the Canadian soldiers would retreat to their own borders, destroying bridges and railways to delay US military pursuit. Troops from Quebec would be sent to seize Albany in a surprise counterattack while troops from the Maritime Provinces would invade Maine. Troops stationed in Prairie Command would attack Fargo and Great Falls and then advance towards Minneapolis. According to the plan, Canadian flying columns stationed in Pacific Command would immediately be sent to seize Seattle, Spokane, and Portland. The Canadians would gain a foothold in the Northern US to allow time for Canada to prepare its war effort and receive aid from Britain. According to the plan, Canada would invade the United States as quickly as possible in the event of war or a US invasion. Within the British Empire, Canadian Army Lieutenant Colonel James "Buster" Sutherland Brown drafted the Canadian counterpart of War Plan Red, Defence Scheme No. Similar plans existed for a 20th-century war with Mexico, although the ability of the Mexican Army to attack and occupy American soil was considered negligible. " War Plan Red" was specifically designed to deal with a British attack on the United States and a subsequent invasion of Canada.
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Seacoast defense in the United States was organized on that basis, and military strategy was developed to forestall a British attack and attack and occupy Canada. Until the early 20th century, the greatest potential threat to attack the United States was seen as the British Empire.
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to declare war on Imperial Germany and enter World War I on the Allied side. When it was captured and leaked to the American press by British Intelligence, the Imperial German Foreign Office's offer in the Zimmermann Telegram to support Carranza's expansionist aims, as laid out in the Plan of San Diego, in return for a potential wartime alliance against the United States, led the U.S. On March 9, 1916, Mexican revolutionary Pancho Villa and his Villistas retaliated for the Wilson Administration's support of Carranza by invading Columbus, New Mexico in the Border War's Battle of Columbus, triggering the Pancho Villa Expedition in response, led by Major General John J. President Woodrow Wilson recognized the latter as leader of Mexico in return for Carranza's "help" in suppressing the Texas border raids. Under pressure from his advisors to appease Carranza, U.S. In order to implement the Plan, the rebels set off the Bandit War and conducted violent raids into Texas from across the Mexican border. The plan also called for ethnic cleansing in the reconquered territories and the summary execution of all white males over the age of sixteen. ĭuring the Mexican Revolution in the summer of 1915, Mexican and Tejano rebels covertly supported by the Mexican Government of Venustiano Carranza, attempted to execute the Plan of San Diego by reconquering Arizona, New Mexico, California, and Texas and creating a racial utopia for Native Americans, Mexican Americans, Asian Americans, and African Americans. After the Civil War, the threat of an invasion from a foreign power was small, and it was not until the 20th century that any real military strategy was developed to address the possibility of an attack on America.
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The American Civil War may be seen as an invasion of home territory to some extent since both the Confederate and the Union Armies made forays into the other's home territory. The Texas Campaign remained the only campaign on American soil, and the rest of the action in that conflict occurred in California and New Mexico, which were then part of Mexico, and in other parts of Mexico. On April 25, 1846, Mexican forces invaded Brownsville, Texas, which they had long claimed as Mexican territory, and attacked US troops patrolling the Rio Grande in an incident known as the Thornton Affair, which sparked the Mexican–American War. After American independence, the next attack on American soil was during the War of 1812, also with Britain, the first and only time since the end of the Revolutionary War in which a foreign power occupied the American capital (the capital city of Philadelphia was also captured by the British during the Revolution). The military history of the United States began with a foreign power on US soil: the British Army during the American Revolutionary War.
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