In 1836, Texas declared its independence from Mexico. For nine years, it remained an independent slaveholding republic, primarily made up of Americans who had immigrated to the area. Texas was finally admitted into the Union as a state in 1845, which upset Mexico. A dispute ensued over the new boundary between the United States and Mexico, which resulted in conflict between American and Mexican troops. The conflict drove President James K. Polk and Congress to immediately declare war on Mexico.

Investigate the source using the zoom and navigational tools in the Flash player and then answer the questions below.

1			Why is a declaration of war important for the president?
2			How does the declaration depict relations between the United States and Mexico?
3			Was it necessary for President James Polk to have Congress declare war?
4			How does this declaration of war differ from others, for example the 1942 declaration of war on Japan?