I personally don't care. Fearing terrorism is a completely irrational fear as the chance of being killed by a terrorist attack is so ridiculously low over here. (I wouldn't want to live in countries like Iraq and Afghanistan though, in those countries terrorism is a very very real danger since the US invaded those countries)
Unfortunately anti-muslim attitudes are getting more and more popular in Europe, so there will however probably be a massive rise of terrorist attacks over here in the future.
But by the way, terrorist attacks with guns seem like a rather strange idea to me. From a terrorist's point of view, I would probably consider bombs to be a much better alternative. They're cheap as well, they can kill more people if placed in the "right" spot, and the terrorist will survive the attack. It seems that most terrorists don't really like the idea of suicide missions.