Oh, I dunno, maybe because that is what the facts of history amply demonstrate? Why do you want to deliberately lie and say that it did?
What possible kernel of evidence do you have that the Declaration was intended by it's authors and signatories to apply to slaves?
I would think that the fact there was not a mass abolition of slavery by all the signatories on the day of the signing ought to be pretty good evidence that it was not, but if that wasn't sufficient, I would have thought that four score and seven years of subsequent history ought to have done the trick.
What we have here with people like yourself, is a Liberal interpretation of History and the "living constitution" phenomena as applied to the Declaration. It means whatever you want it to mean, because you change it's meaning after the fact to suit your own preferences.
But we're not talking about the facts of history. We're talking about inalienable, self-evident rights.
What possible kernel of evidence do you have that the Declaration was intended by it's authors and signatories to apply to slaves?
Hey, Justice Taney! Lookin' good!