Why did James K. Polk sign the joint resolution annexing Texas?

Answer 1

James K. Polk signed the joint resolution annexing Texas in 1845 primarily to fulfill his campaign promise of expanding the United States' territory and to promote the idea of Manifest Destiny. He believed that annexing Texas would enhance national security and strengthen the economy by adding valuable land. Additionally, the annexation was seen as a way to address the issue of slavery, as Texas was a slave state, thereby aligning with the interests of Southern Democrats. The resolution ultimately reflected the growing sentiment for westward expansion among Americans during that era.