The Impact of Manifest Destiny upon U.S. Foreign Policy

Manifest Destiny and Foreign Policy The term "Manifest Destiny," which American writer John L. O'Sullivan first used in the New York Democratic Review in 1845. , describes what most 19th-Century Americans believed was their God-given mission to expand westward, occupy a continental nation, and extend U.S. constitutional government to unenlightened peoples. The idea was the driving force behind the rapid expansion of America into the West from the East, and it was heavily promoted in newspapers, posters, and through other mediums. While the Manifest Destiny was not itself an official government policy, it had a critical impact on the foreign policy of the U.S. and encouraged Westward colonization, territorial acquisition, and American thought during the 19th century. Westward expansion A.K.A. “Manifest destiny” led to America’s rapid acquisition of the old Mexican Southwest and the Oregon Territory that marked the fulfillment of President James K. Polk's expansionistic campaign promises. Polk ran on only one platform -- westward expansion. He wanted to officially claim the southern part of Oregon Territory; annex the American Southwest from Mexico; and annex Texas. Thus, Polk’s desire for land would eventually cause a great deal of suffering for many Mexicans, Native Americans and United States citizens. Following the earlier Texas War of Independence from Mexico, tensions between the two largest independent nations on the North American continent grew as Texas eventually became a U.S. state. Disputes over the border lines sparked military confrontation, helped by the fact that President Polk eagerly sought a war in order to seize large tracts of land from Mexico. The war took place mainly on Mexican soil. Partially because of disorganization and instability in the Mexican government, the war resulted in and American victory. The Treaty of Guadalupe Hidalgo, ending the war, made the southern boundary of Texas the Rio Grande, gave California and New Mexico to the