From 1846 to 1848, the United States and Mexico were at odds in the Mexican-American War. It followed the annexation of Texas by the United States, which Mexico deemed Mexican territory. It can be observed that Mexico never declared war on the United States, but rather the need to defend the country’s territorial integrity and repel an invasion by the United States. Analyzing the preceding decrees, I believe that the war was unjustified because it was precipitated by Polk, who stated, “We must always mandate the principle that the people of this continent alone have the right to decide their own destiny.” The war was also illegitimate because of Texas annexation and the development of slavery in Texas. Even though the US president supported the war, Lincoln believed otherwise, he stated, “Whether the specific spot of earth on which our citizens’ blood was poured was or was not our own soil.” According to Lincoln, the conflict was merely a desire for state inversion, and the Mexicans defended the country’s geographical integrity and resisted the United States.
The term “Manifest Destiny,” which originated in 1845, refers to the belief that the United States is predestined by God to expand its rule and disseminate democracy and capitalism across the whole North American continent. The ideology played a significant role in igniting the war by inspiring a number of methods aimed at removing or destroying the indigenous inhabitants. “Under the graces of Divine Providence… it becomes us, in humility, to make our ardent acknowledgments to the Supreme Ruler of the Universe, for the incalculable civic and religious blessings with which we are favored,” writes James Polk. He felt that white Americans were divinely destined to settle the entire North American continent.