The Mexican-American war was one of the main armed conflicts of the 19th century that established the US as the dominant force in the region. The US politicians were looking for an opportunity to expand the territories for some time, and the Texas Declaration of Independence gave them an opening. While technically Mexican-American war can be considered an example of the US aggression, it would not be possible without a number of political missteps from the Mexican side.
In the years preceding the separation of Texas, Mexican immigrant-friendly policies resulted in the mass migration of the US citizens to the state. While differences in culture and religion were already a serious issue, the anti-federalist movement’s victory in the 1835 Mexican elections was the final straw. The new government implemented the laws that did not consider the Texas population’s interests and ignored the fact that Mexicans became the minority in the state. The Texas Revolution started the chain of events that ultimately led to the war between Mexico and the US. Nationalistic attitudes certainly played an important role in the US governments’ decision to annex Texas. While many prominent intellectuals of that time did not approve of Manifest Destiny, the majority of the population has shown support for the imperialistic ambitions of Polk’s government. For the Democrats, Manifest Destiny was merely an excuse to achieve economic and political goals by acquiring the new territories.
While the US obtained large territories as a result of the Mexican-American war, many politicians, including Lincoln, criticized the decision of the government as unjust. In my opinion, the expansionist policy of Polk’s government largely contradicted the principles and values that define the American nation. However, from the historical point of view, this war was definitely beneficial for the US. It is also important to note that it laid the groundwork for the political turmoil, which led to the Civil War and the abolishment of slavery.