Matthew Yglesias says (emphasis mine)

It’s precisely because of stances like this that it’s very hard to take the “abortion is murder” crowd seriously when they say abortion is murder. Their revealed behavior indicates that they don’t actually find abortion especially problematic, but just place it on a spectrum containing a general aversion to women controlling their own sexuality

...

Atrios sees this as a reason to mock those who advocate seeking “common ground” with abortion proponents. I think we’re arguably seeing here the real fruits of seeking common ground in good faith—their real views are smoked out.

He said it here.

Atrios is technically correct that seeking compromise never works with ideologues. But Yglesias is absolutely correct that simply making the effort forces those ideologues to show their true colors.

Which, since they’re very ugly colors, drives a wedge between them and the vast, vast majority of Americans for whom efforts to prevent unplanned, unwanted pregnancies through contraception, sex education, and empowerment for girls and women, are perfectly acceptable.