I'm not claiming to have high ideals. I'm sure I've mentioned before on this site that one time I was on a bus, probably a few weeks after 7/7, and some man who looked Muslim got on and my first thought was indeed "crap, he's got a bomb and I'm dead". So I do understand the reaction and I still know that it's irrational. That man, like almost everyone else, never has had and never will have the intention of blowing himself up along with those around him. To assume otherwise can't be defended as sensible fear but is unreasonable prejudice.
For all the coverage that terrorism gets we've had very few (successful) attacks on these shores. A certain level of vigilance is obviously vital but if it gets to the point that you are automatically assuming that your life is in danger every time you are near to a Muslim then it's gone beyond the rational and into paranoia, and that is far more damaging than the attacks themselves.
But the larger point is that this is nothing new. Sadly it doesn't take much for people to turn against and fear each other. We've seen that again and again in history. The Islamic brand of terrorism is only the latest example, and it won't be the last.