Same as RevWar.
If they wanted to leave, let them leave. Why “union” at the point of a gun?
Walking out without negotiation, without paying for your share of national obligations, taking every piece of property you can get your paws on, and shooting up a fort on the way out the door are not actions that promote an amicable separation. The South wanted their war, they got it. Sorry it didn't work out the way they had planned.