The North won the civil war in no small part because its economy was far more diverse and far greater than the South's. It was far more industrialized. In other words, they did capitalism better than the South.
Slaves outnumbered Slavers scores to 1, and it wasn't the guns that kept them in check - it was psychology.
Racism is psychological and the people who convinced you Socialism is the way are the same ones looking to short circuit the capitalist system that allowed them to advance. Cause that's how you win this game of thrones, by being the only one who gets to choose.