I was speaking to a friend of mine this afternoon about this, and he raised a point I'm not sure has been discussed all that much (though I haven't read much in the meejah, maybe it has). He said that the reason people feel a nebulous uneasiness about the veil, is because face-covering in our culture has traditionally been the preserve of criminals and those who were up to no good. Hence the need for men to uncover their heads when they went into churches, for example, to show openness (translated into respect for God). He was also saying that when he addresses people in Summer when he's wearing sunglasses, he takes them off so that they can see his eyes, out of politeness. "It's about communication, innit?" he said. The uneasiness at the sight of the veil, his point is, is a residual gut feeling born of very strong cultural traditions, which up to now haven't really been acknowledged or examined that much, as we take our own culture for granted.
I remember reading a while ago about how in the Carribbean, it's respectful to lower your eyes when an adult addresses you. Hence the frustration of teachers in Britain ("Look at me when I'm talking to you") at a perceived disrespect, when in fact it's not intended.
Could it just be that we have a very strong culture in Britain of looking each other in the face to show our honesty and openness (looking away, averting your gaze, is often described as "shifty" in our culture, where it might be described as "respectful" in another), which simply clashes with cultures where lowering eyes, covering faces, etc. means something different?
If so, then I think it's a good thing JS raised it, whatever his motivation (and him being a politician I'm happy to go along with those who say it probably isn't a good one). The more we're aware of our own gut reactions and why our cultural traditions should engender them, and of those of others, the better the communication between us, imo.