Lincoln’s emancipation policy ultimately meant the end of slavery in North America. The point that it didn’t free them immediately is a bit silly: within three years, they were all free.
Lincoln said it was a war measure. Harry Jaffa says that was just another lie in what had been an unbroken string of lies by Lincoln to hide from people that he really had always intended to abolish slavery. There is of course no way dispositively to disprove that he had always intended to do what he finally did, but there’s no proof other than that he ultimately did it to support that he had always intended to do so. It’s hard to believe that anyone could have been so committed a liar for decades on end, but you can believe that if you’d like.