Once Congress agrees to regulate one sort of abortion because it is gruesome, the pro-lifers will immediately turn to another form of abortion and insist that it, too, be regulated, because it, too, is gruesome.
The pro-lifers will immediately turn to another form of abortion, once congress agrees to regulate one sort of abortion for the reason of it being gruesome.
Once Congress agrees to regulate one sort of abortion, it will shut the pro-lifers up for good.