Here's a fabulous rebuttal to Gary Wills, who recently informed the faithful that abortion is "not a religious issue." Darn right it's not "religious." It's a basic human--and therefore all-encompassing--issue.
This op-ed is particularly run because it has quotes from as way back as Clement of Alexandria, instead of the old "Aquinas says so." It also explains how determinative your view of unborn humans is for your view of all humans.