Convincing me of that is a bit easier than convincing the fanatics who led the South into its disaster. Lincoln would have done nothing against slavery not allowed by the constitution. While it did not protect slavery it also did not ban it and a constitutional amendment would have been required and probably would have been impossible to achieve.
They realized that without a fedgov which was pro-Slavery and which would allow expansion their system was doomed. The only question was how long it would take. That is why they tried so desperately to force a pro-slavery constitution on Kansas.
chattel slavery was DYING an UNlamented death. agricultural mechanization would have killed the system off with a decade or LESS.
a MILLION lives, needlessly lost (especially given that MANY THOUSANDS of those lives lost were "persons of colour"), in a war of damnyankee aggression against the new CSA republic was a VERY high price to pay to hasten the demise of slavery by 6 or less years.
the WBTS was NEEDLESS, provided that lincoln & his coven of radicals were smart enough to let the southland go in PEACE. SADLY, they were too power-hungry & too STUPID to do that.
free dixie,sw