In the 1840s, the U.S was struck with the idea of <em>manifest destiny</em>. An idea that America should control North America from the Atlantic Ocean to the Pacific Ocean. Mexico had the legal right to Texas thus dominated California, Arizona, and New Mexico. Two territories stood in America's way of accomplishing the manifest destiny idea; first, the Oregon Territory that was occupied by both Great Britain and the United States and the Western and Southwestern areas owned by Mexico. The differences between the United States and Mexico over the border of Texas led to the Mexican American War that resulted in American gaining ownership of Arizona, California, New Mexico, and Texas. The ownership of these territories fulfilled the '<em>Manifest Destiny' </em>of the U.S stretching from the Atlantic to the Pacific, Manifest Destiny.
