QUOTE integrity, END QUOTE
John, this is at the root of the problem in the American church -- a lack of integrity. Most people think of a lack of integrity as being caught in some great moral fault as with Ted Haggard and others. But, integrity refers to "being whole" (as in an integer being a "whole" number).
Christians compartmentalize their religion into very distinct secular and sacred boxes. They confine their religion to "safe houses" (sometimes called sanctuaries). We fail to adequately "integrate" our principles into marketplace practices. Thus, abortion is being sustained by Christians with no integrity moreso than pagans with no morals.
Where are the Wilberforces today to set people free from the abortionists? Sadly, you will see very little challenge -- as you point out -- from evangelicals because their lack of integrity means that their religion stops at the sanctuary exit.