Appeasing foreign powers. They thought that they would eventually stop asking for more after they were given enough, but as we know it today, hitlers only plan was expansion across all of Europe.
Do you not know them or are you just being lazy?
The main reason as to why the southern planters has opposed to the wilmot proviso was because of the reason that if they don't oppose to it, it would likely abolish slavery in terms of the lands that they have gained from the Mexican American War.
