0-for-history: The track record of 'human non-personhood'

Defenders of abortion and embryo-destructive research argue that unborn human beings do not bear a right to life -- that is, to use the popular term, they are not "persons," beings deserving of basic moral respect, like you and me.

There are many (decisive, it seems to me) reasons against supposing that only some members of the human species are "persons" (and, as such, ought not be killed except arguably in very narrow circumstances, such as just war or self-defense) and other members of our species are not (and thus may be killed for the convenience or possible benefit of others). But here is an additional consideration.

Often throughout human history some human beings have classified other human beings as "non-persons" who may therefore be treated without the dignity and respect that is owed to persons. Blacks, Native Americans, Jews, women and many more groups have at times been excluded from the human family and mistreated (or worse), their fundamental rights as persons denied. And every single such occurrance in history -- every instance of deciding that some human beings are not persons bearing basic rights -- is now almost universally considered a horrific moral mistake that led to utterly horrific consequences. Every single time, without exception.

Really?

But pro-choice bioethicists and philosophers think that the streak has finally ended, for they have at long last, against all odds, found some human beings who don't count as persons and whom we may kill and discard for our convenience, or if we think harvesting their parts might be interesting or useful.

Really, people? (They are people, I take it.) History should give them more than a little pause.