I doubt it would play out that way, but that's irrelevant.
Too complicated a scenario to play out in our hypothetical engagement.
But look at what happened last time. When South Carolina seceded.
During the crisis over Fort Sumter, Congress tried to find a compromise that might prevent war. Lawmakers proposed a new line across the country. South of the line, slavery would be permitted. North of the line, slavery would be illegal.
Many Republicans supported the proposal, even though the Republican Party opposed the spread of slavery into the western territories.
One Republican, however, rejected the idea completely. He was Abraham Lincoln, who would take office as president in March. Lincoln said there could be no compromise on extending slavery. "If there is," he said, "then all our hard work is lost. If trouble comes, it is better to let it come now than at some later time."
Today there is no moral issue like slavery for the North to hang a war on...
In fact, the South would likely have the moral issues, like abortion.
And there is no Lincoln to hold the line.