I personally detest the modern scientific thought-frame that its just "a clump of cells". That terminology seems Orwellian to me, and is a slippery slope to quickly dehumanize the subject.
I'm in favor of a choice to abort in special circumstances such as rape or mental defects, but then again that simply opens the door to more loosely defined slopes. Its like...where do we draw the line? Its either 100% yes or 100% no.
It bites me that a lot of people who support abortions don't really think about these eugenic consequences, whether they are intentional or not. 21 million babies in roughly 50 years, that is a damned tragedy. Couple that with the rapid influx of immigrants who are encouraged by the system to reproduce as much as possible and voila!
Genocide, but we did it to ourselves.
I read things about black markets dealing in fetuses and infant parts, and it sickens me. I don't want to take a hard-line stance against abortion across the board, because I've been there...done that...and I have nobody else to blame except myself for not being in a situation where I was prepared to support something I created. I hate myself for allowing it to happen, but at the same time I know we are in an easier place in life because it happened. I treat sex with respect now, because that is a damned force of nature you're playing with.