USA HISTORY

Detailed explanation-1: -In late April 1846, Mexican troops crossed the Rio Grande and killed eleven U.S. soldiers. In response, Polk requested a declaration of war from Congress, arguing that Mexicans had “shed the blood of our fellow-citizens on our own soil.” By May 13, 1846, both nations officially were at war.

Detailed explanation-2: -General Zachary Taylor receives orders from Polk to move his troops from Fort Jesup in Louisiana to a position “on or near the Rio Grande” in Texas to discourage a Mexican invasion.

Detailed explanation-3: -President James K. Polk had accused Mexican troops of having attacked Americans on U.S. soil, north of the Rio Grande. But Mexico claimed this land as its own territory and accused the American military of having invaded.

Detailed explanation-4: -Polk had a three-part plan for the war with Mexico: First, American troops would drive Mexican forces out of the disputed border region in Texas and make the border secure. Second, the United States would seize New Mexico and California. Finally, American forces would take Mexico City, the capital of Mexico.