As both a recent ex-serviceman (who has carried fair number of coffins both in the aircraft and on my shoulders) and a resident of Wootton Bassett I too was horrified to read the story, but then a few thoughts kicked in......
These "groups" thrive on publicity, they provoke to get the publicity that enables them to "persuade" others to join them. The " debate" on any ban actually fuels their cause regardless. If they are banned then they get a massive "we are downtrodden/picked on/racist/whatever" publicity boost
One of the prime reasons for the
initial war on the Taliban was the lack of freedom imposed by that regime on its citizens, the oppression and belittling of women in particular. The whole tenet of "western" philosophy is "freedom of speech" and the "right to protest"
If we "ban" this proposed "march" .. and lets face it it is only proposed at the moment ... are we not being rather hypocritical ?? Do we not give fuel to these folks

Would we actually turn an "idea" into a "reality" simply by talking about it

I honestly don't know the answer .... but I have a horrible gut feeling that my town, my sense of "right and wrong" and my ideas of "freedom" will all be tested ..... and everyone will lose something .. even if it is only our dignity.