“People have a right to self determination. Having a bad reason for wanting independence is not justification for denying them their rights.”
So a massive slave insurrection in the deep south could be justified on those principles.
I'm not going to indulge everyone's efforts to keep making the people nobody gave a sh*t about for "four score and seven years" of Union slavery, the focus of the discussion.
I am also not going to attempt to justify murder, which is what would have happened in such a circumstance.
The black people had a right to freedom, but one does not prove subjugation is wrong by forcing subjugation on others. That proves subjugation is "right", if you have enough power. It is the same foundation on which slavery is built.
The plantation owners were wrong to compel labor from others, but this isn't the reason why the Union went to war with those states. That is the excuse used to justify what they did after the fact of already launching the war for other reasons. Monetary reasons.
If his peculiar form of logic is to be followed, it would also by extension legitimize John Brown and his band of merry men.