On the Republican Party's Opposition to Slavery in the Territories

It had absolutely nothing to do with morals and everything to do with keeping black people out; a) because they didn't particularly like black people and b) because they didn't want to compete with them (for their labor). This whole concept of an enlightened North trying to bring the South more into modernity is an absolute absurdity and all that you really need to know here is that a) black people weren't even allowed into the state of Indiana (yeah, that's right, it was illegal simply to be black there) and b) New Jersey had legalized slavery all the way to 1865 (after 1846 slaves were called "apprentices for life" but make no mistake about it, they were slaves).