[yyjiqflo] Why didn't money prevent the Civil War?

Why did the American Civil War occur?  In particular, why did it occur when it did?

On the eve of the Civil War, the price of cotton was very high due to (I think) high demand, so cotton plantations in the South were highly profitable.  Surely some of those profits could have been invested into avoiding civil war.  War is costly, so avoiding it is a good investment.

Money can solve political problems in many ways.  Underneath the table, money could have gone toward greasing politicians toward favoring policies that avoided civil war.  Above the table, they could have enacted some legislation that taxed cotton profits and redistributed the income to the North, making the North less willing to disrupt the Southern way of life, the Southern method, namely slavery, of generating the tax revenue the North could have enjoyed.  Even the moral outrage of slavery could have been partially mitigated when there's money available: enact legislation that decreases the mistreatment of slaves.  Such regulations presumably would have induced additional costs to slaveowners (maybe the slaves become less productive), but when profits are flowing in, people don't oppose too much some extra cost.  The extra cost would be just like a tax, ultimately just an investment to avoid the greater cost of civil war.

In general, there's incentive to keep slavery only if there are economic profits in keeping the institution.  Some of those profits could have been spent on avoiding civil war.  (Because this general argument relies on economic (not accounting) profit, it could be true even if the selling price the agricultural output were low, even if the plantation were losing money in the accounting sense.  One just needs a gap between the cost of slave labor versus the next best alternative, presumably wage labor.)  (We still need to think through how to incorporate civil war into a framework of economic profit or loss.)

Maybe Southerners incorrectly estimated just how costly civil war would end up being.  But that would be a little surprising: information was likely available about the costly large-scale French wars in Europe which had then only recently concluded.  Maybe they incorrectly estimated the probability that war would occur.