Well, I certainly hope Canada doesn't go this route, although Quebec is making threatening noises.
The solution to the niqab "problem" is simply time. Those few hundred women who for one reason or another wear the thing will have daughters, and those daughters will naturally choose to dress provocatively, dye their hair green, and listen to crap music while chattering away brainlessly on their I-phones...just like their white counterparts.
Plus, I have trouble with the idea of "defending society" by essentially picking on a tiny sub-set of the women-folk from one of your minority groups. It smacks of cowardice, of finding an easy target. I mean, this is France: if we were talking a couple hundred men wearing masks the country would have already surrendered.