DiogenesLamp likes to wave around the "Corwin Amendment" as if it was a cross to protect him against Dracula.
It's not, it's just another Democrat false flag operation -- conceived & proposed by Democrats like Mississippi Senator Jefferson Davis, pushed through Congress by Democrat President Buchanan and signed by him against the majority of Republicans in opposition.
Now, typical of Democrats, they wish to blame it on Lincoln to buttress their claims that Confederates were actually good conservative Republicans and Lincoln really a radical Democrat.
Typical.
If it were about slavery, the President wouldn't be supporting an amendment to protect slavery.
All of your subsequent arguments are rendered moot by pointing out the contradiction implicit from his support for the Corwin Amendment.