I can understand Muslim women wearing an outer gown and head covering (be it scarf, or shawl, etc) but on what basis they claim Niqab is Islamic. Nowhere the Qur'an mandates it. In fact in a verse the Messenger is told not to marry any more women even if their Husn (outer/inner beauty) attracts him!!
Is Niqab not an innovation in Deen? Why do women not wear it during the world's largest mixed gathering: Hajj?
In some countries (like Pakistan) some women engage in all kinds of immoral activities as the Niqab protects their identity. How convenient!!
Sure, women have a right per law to wear what they like but to claim a certain right based on religion must be justified. If it is a personal choice to wear Niqab then it should not be claimed as religious right because it is not!!
In the West, if the idea of a women wearing Niqab is to avoid attention, well, it fails miserably on this account alone as she does gets attention and lots of it (mostly negative)!. If she was dressed up modestly nobody would even notice here going about her business. Some have termed the Niqab as extremists' battle flag of in-your-face defiance!!
Moderation means middle way. Don't go semi naked but aslo don't cover yourself like a walking tent with slits.
Deen must be applied with wisdom otherwise instead of Rehmat it becomes Zehmat.