Abortion is the same way. If we have some states that allow it, and some states that don't we're just gonna find an influx of people who travel to other states specifically to get abortions, or worse, just stay in state and do it less than legally. That's the issue here. People are going to get abortions, that's a fact of nature, if we allow it, we're at least allowing a way to do it safely, without harming the person getting it. Leaving something like that up to the states would end up hurting people in the end.
Then I'd say it's up to those people whether or not they want to risk that. Granting it everywhere will result in more Westborough Baptist Church-like protests and acts, and banning it everywhere will remove that much more liberty from people and cause an even more unsafe procedure to those who choose to do it anyway. Leave it to the states at least and people will have somewhere they can go and have it done.
The rest of that post I didn't respond to on a flat disagreement of value, and the church part I do agree with for the most part. That's a political argument though, I suppose.
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