What connections did opponents of the u. s. war with mexico make between the war and slavery

While driven by economic ambitions and a sense that the United States was "destined" to span the entire continent, the war also raised the issue of how acquisition of such a large territory would affect the balance between slave and free states. The congressional response-the Great Compromise of 1850-not only allowed for the possible creation of new slave states, but also placed legal demands upon northerners to aid in the recapture of fugitive slaves.

Expert Answer: More states: more opportunities for slavery to spread, which was supported by many, but many also feared the idea of mor slave states being added.