USA HISTORY

Detailed explanation-1: -When the Mexicans fired on American troops in April 25, 1846, Polk had the excuse he needed. He declared, “[Mexico] has invaded our territory and shed American blood upon American soil, ” and sent the order for war to Congress on May 11. The act was a questionable one.

Detailed explanation-2: -Polk asked Congress for a declaration of war against Mexico following a skirmish between U.S. and Mexican troops in disputed territory. In his message to Congress, Polk claimed “Mexico has passed the boundary of the United States, has invaded our territory and shed American blood upon American soil."

Detailed explanation-3: -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-4: -Polk, in turn, declared the Mexican advance to be an invasion of U.S. soil, and on May 11, 1846, asked Congress to declare war on Mexico, which it did two days later.