I don't know. I wouldn't support it because it is easy to imagine it as a kind of hate speech. It would be stupid though, because people would definitely let you know how they felt about such garb. More power to them, I say. 

But again, you make a false equivalency. How is a KKK hood and a freely chosen niqab the same? I can see why a black person would be harmed by a troop of KKK people on the subway. How are you harmed by a group of women with a niqab?