But you agree the Emancipation Proclamation was justified and you think Lincoln was right to do it, right?
This point has come up before, but perhaps you've missed it. Grabbing slaves as a war effort is perfectly legitimate if it is a "war." Meaning a conflict between nations. If it is a "rebellion" then constitutional law still applies.
That is the legal argument. The moral argument is that slaves should not be slaves, and when one has the opportunity, one frees them.
But i'm no longer convinced Lincoln was motivated by moral sentiments. One does not urge the Corwin amendment be passed, and then claim the moral high ground on freeing slaves because it is the right thing to do.
I think Lincoln's emancipation proclamation was more about winning, and less about doing the right thing.