I would most possibly do the same thing, or take the south back to US as brothers, but I might also add a little punishment. The punishment would be limited import for a period of years (1, or 5). I would also not allow them to vote or participate in any political meeting, congressional decisions, etc.
Hope this helps, you might have a different opinion however, but as I think, it would be better to punish them for
1. Not obeying the rules (still having slavery)
2. Electing a secondary president.
3. Helping the war happen.
4. Trying to become independent from the rest of US.
<span>the environment sets limits on what is feasible but does not dictate a culture's choices.
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There were many factors that allowed the Byzantine Empire to last a 1000 years after the end of the Roman Empire which include the fact that Constantinople, the capital of the Byzantine Empire, was protected with walls that lasted almost the entire 1000 years, making Constantinople, and the center of the empire's economy/culture impervious to invaders.