When Lincoln issued his emancipation proclamation he knew it did not have the power to end slavery. Why was he correct?

Since the South seceded from the Union they were no longer in the same country. The Union laws didn't count for anything in the Confederacy. So Abraham was just trying to get the slaves from the south into the Union ...

The south had susceeded from the union rendering any union law useless, but garunteed freedom if they were to come to the union, inspiring many to fight back