Hodge and Christ dying for all men

It's pretty well established that Hodge believed in an 'unlimited' atonement, but something that he said surprised me. In volume II section 4 - Philological and Moral Evidence (of a common ancestor) while talking about the evidence that we all descended from a common pair of people Hodge says this

Christ died for all men, and we are commanded to preach the gospel to every creature under heaven. Accordingly nowhere on the face of the earth are men to be found who do not need the gospel or who are not capable of becoming partakers of the blessings which it offers.  The spiritual relationship of men, their common apostasy, and their common interest in the redemption of Christ, demonstrate their common nature and their common origin beyond the possibility of reasonable or excusable doubt."

This astonishes me because here I am going around trying to show that because Christ dies as a man His death is good for all men, while the hyper-Calvinists are saying He died only for the elect. Much like atheists of old the modern Calvinist is asserting that there is a separate kind of humanity, a separate, unsavable group. Yesterday the eugenicists were saying it was black people; today it's the non-elect.
But even more startling, I'm using the shared humanity to prove unlimited atonement, yet 150 years ago it was completely the other way around. People were using the death of Christ for all men as proof that all men come from Adam.
How far we have come in accepting the truth, only to backslide all the way down the hill.