The Supreme Court is hearing a case about a Massachusetts law barring protesters from entrances to abortion clinics. If it’s upheld, unions and environmentalists could be next. The Supreme Court heard oral arguments Wednesday for McCullen v. Coakley, a case in which anti-abortion activists argue that their First Amendment rights have been violated by a 2007 Massachusetts law that bars any person from entering or staying in fixed 35-foot-buffer zones around entrances to abortion clinics.By “any person” they mean “any person who says something negative about abortion,” because there are exceptions for people going into or coming out of the...