If I’m not mistaken, the Civil War was fought to preserve the Union... and slavery became an issue as the war went on. The Republican party was created as the party for ending slavery... still is. I don’t really understand what Fox is trying to say here between the lines.
Your right about that, it really made no sense to mention Lincoln in there and it just muddied the water with a historically inaccurate & inflammatory references.
Lincoln was no more interested in liberty than he was in the southern right to self-government. He made this abundantly clear in his repeated statements on the subject to his “countrymen” in explaining his war.