i mean, im just reading the opening paragraph of the wikipedia article
The Mexican–American War,[a] also known in the United States as the Mexican War and in Mexico as the Intervención estadounidense en México (United States intervention in Mexico),[b] was an armed conflict between the United States and Mexico from 1846 to 1848. It followed in the wake of the 1845 U.S. annexation of Texas, which was not formally recognized by the Mexican government, who disputed the Treaties of Velasco signed by Mexican caudillo President/General Antonio López de Santa Anna after the Texas Revolution a decade earlie