"To what extent did the debates about the Mexican War and its aftermath reflect the sectional interests of New Englanders, westerners, and southerners in the period from 1845 to 1855?"

I know some of the debates of the war, but I don't know how they reflect sectinoal interests:

-Manifest Destiny
-Annexation of Texas
-Slavery vs. Nonslavery in new territories (Wilmot Proviso)
-Polk's reinstallement of the Independent Treasury
-Polk's veto of the Rivers and Harbors Bill of 1846

That's all that I can come up with, and obviously five points isn't enough for an FRQ. If anyone could explain what those had to do with sectional conflicts, as well as giving a few more ideas to include, it'd be greatly appreciated!

-edit-
Also, if this isn't the right direction that I'm going in, is it possible for me to say something like: "The Mexican War reflected some sectional conflicts, but the majority of the problems came from political divisions." (or something like that?)