Hurray! Steve Waldman gets it!
"The basic hunch that what's growing in the womb becomes more human as days roll by comports with what we know, or think we know, about human development. An embryo is a clump of undifferentiated cells. At week six, the heart is no bigger than a poppy seed but has begun beating. At 12 weeks, the fetus is just 2.5 inches long, but can wiggle toes and fingers; the brain is developing. At week 20, the fetus is exercising its lungs. At 22 weeks, some babies could survive if delivered prematurely. And any time in the third trimester, they're practicing breathing, listening and reacting to stimuli, doing many things a post-birth baby does but doing it indoors instead of out.
This belief that life within the womb is on a continuum is not explicitly reflected in the political debates about abortion. We debate whether we should have parental notification--not when we should have it. We question politicians on whether they'd provide government funding for abortion, not ever asking whether subsidies should be provided for early abortions but not late. ...
... Instead, an abortion policy matching the values implicit in the polls would focus less on rights or numbers and more on timing. Success would be measured on the basis of moving abortions earlier in the gestational cycle--even if that conceivably means more overall abortions. It would be not about whether, how or how many, but when. Not "safe, legal and rare" as Bill Clinton once said, but "safe, legal and early." from Steven Waldman from BeliefNet.
Now, if only our political discourse could follow this line of reasoning.