The manifest destiny was the American conviction that Americans had the right to expand U.S. territory from the Atlantic to the Pacific Ocean. Among the Americans who strongly supported this belief was President James K. Polk and as a strong advocate of manifest destiny, he pushed for the annexation of Texas and additional territories from Mexico, and Oregon territory to appease Northerners. The Democratic party, the party from which Polk was from, remained adamant about increasing territory to uphold southern needs. Because of manifest destiny, presidents such as Polk (Texas and parts of Mexico) and Pierce (Cuba) strived to expand territory despite large opposition, and military filibustering that later arose contributed to opposing political …show more content…
With Polk’s narrow victory, the Democrats immediately called to admit Texas as a state, but was only successful by using a joint resolution,which included admitting Oregon as a state to satisfy Northern expansionist desires and balancing the number of slave-owning and free soil states. Not satisfied with these states alone, Polk turned to Mexico’s northern provinces (such as California and New Mexico) and endeavored to start a revolution in California. Polk’s audacious move to incite a revolution in California--done by sending Thomas Oliver Larkin to influence famous Californios to seek independence, seizing San Francisco Bay, and employing John Slidell to try to buy California--was met with greater tensions between the U.S. and Mexico for a war. These acts led to Polk utilizing more aggressive tactics to expand U.S. territory; Polk sent General Zachary Taylor to occupy disputed territory and “provoke a fight” (Pg. 419 Henretta), and the war concluded with American triumph. The war had started with patriotic expansionism, but soon divided the nation: the Whigs, who were against the war and did not support “this wretched cant about a ‘manifest destiny’” (Pg. 421 Henretta) as stated by New York Senator William Duer, and the Democrats, who they themselves were split into antislavery and proslavery Democrats. As a result, manifest destiny divided opinions on the Mexican War and how political parties perceived territorial