Where is the center in the abortion debate?

Ross Douthat:

“So yes, there are more Democrats who vote for partial-birth abortion bans, for the born-alive laws, and for limits on government funding of abortion than there are Republicans who vote against the pro-life cause on these issues. But saying that the Democrats are a big-tent party on abortion because they tolerate members who vote against partial-birth abortion is like saying that the Republicans are a big-tent party on the environment because they tolerate members who would vote against, say, dumping radioactive waste in drinking water: It implicitly accepts a very pro-choice reading of what counts as the middle on abortion, and what counts as the extremes.”

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“If you're like me, and think that any middle-ground, "compromise" position on abortion would have to entail returning control over abortion policy to the legislative branch, and implementing, at the very least, more European-style restrictions on second and third-trimester abortions, then the GOP looks like a bigger-tent party than the Democrats. But if you're a pro-choicer who believes that the Roe-Casey settlement is already a middle-ground take on abortion - a sensible-centrist alternative to the anti-abortion extremists who would have the government ban the practice and the pro-abortion extremists who would have the government actively promote it - then I suppose that yes, Democrats are going to look like the bigger-tent party.”