There is actually now no known way how to deal with Islamic radicals. Ones say killing them out is the way, others say eat them from inside, as well as another voice is to let them be and they will naturally liberalize...
Every religion had some reforms, so maybe also Islam will have. Don't remember the Crusades? That was then also somewhat a terrorism not unlike to nowadays al-Qaeda attempts... Different times, different ways of gaing the goal, same (stupid) ideas.
This is getting serious, reminds me a bit the late 30's in Germany, when the Nazi movement was on its rise. We are 60 years after the WWII and you can still see neonazis with their little polished baldheads running around...
So, the Islamic radiscals won't disappear, we just need to get used to live with it, try to prevent it as much as possible and know how to behave not to take a risk. E' is absolutely right, he knows by experience.
BTW, see my banner.