For me it has much more to do with a state standing up and saying 'You people have to do as everyone else does here' before that group gets so separated from the rest of us and is seen to be given special treatment (just because of its religious customs). I'm glad to see some of our European neighbours are braver than us in making this initial stand. Let's hope it quickly spreads right across Europe, because that's what usually happens, two or three start a policy and then the others feel brave enough to follow them.
And from a practical point of view it is necessary to ban it too. Remember that male terrorist who escaped Britain wearing one?!
And lastly, yes, the sexual politics angle - it can only do these women good to force them to face the public with nothing to hide behind. Hopefully it can start the long process of them achieving more respect and equality within their own horrendously patriarchial society.
And they must be forced to accept that our society, the society of our land comes before their own enclave.