After World War II, the Soviet Union and the United States were the two most powerful countries left in the world. The Cold War was a period of tension between the two countries over ways of life. The two countries tried to get other countries on their side.
In 1846, the United States and Great Britain signed the Oregon Treaty. In this treaty, Oregon Country was split with the U.S. gaining sole possession of the territory south of the 49th parallel, and Great Britain gaining sole possession of the land to the north.10.In 1853, the United States sent diplomat James Gadsden to Mexico to renegotiate the border between the U.S. and Mexico.. From 1818 to 1846, the United States and Great Britain administered the territory in Oregon together. This was a compromise until both countries could agree on how to divide the land between them.
The United States instigated the War of 1812 by declaring war on the British Empire. The first assault was led by American general William Hull, who crossed over the Detroit R â¦ iver in May of 1812 and occupied the town of Sandwich.he US knew that Britain could spare very few troops to defend Canada. One of the objectives of the US in starting the war of 1812 was to acquire Upper Canada and Lower Canada and annex them into the US. There was no interest in crossing the Atlantic to attack Britain, and there was little to be gained by doing so.