Why were some against the annexation of Texas?

Answer 1

Controversially, instead of annexing Texas into the United States by treaty, which was the proper protocol, the United States decided to annex it by a simple majority vote in Congress. As a result, the legality of the annexation was questionable.

Answer 2

1) it would enhance the slave power (upsetting the slave state/free state balance)

2) it would bring war with Mexico and possibly England

3) it amounted to a landgrab that was counter to U.S. principles of democracy

4) unconsitutional - the U.S. Constitution disallowed annexation (at least in the manner proposed)

5) annexation was a threat to national unity --since the Northern sentiment against it was so strong (see reason #1!)

Answer 3

Because from an International point of view Texas was a break away state of Mexico.

Answer 4

It added a slave state, which altered the Nation's political make up.

Answer 5

no