Suicide terrorists are like roaches. There are way more than the ones you see because they are always hiding You can never hope to scare them off, none of them are smart enough to be afraid of you. Sometimes you can kill them when they come out into the open, but that doesn't happen very much and often you don't see them until it's too late. You can devise ways to kill them where they hide, but as stupid as they are, they still find ways to adapt.
The best way to deal with roaches and terrorists is to deprive them them of what they feed on. Roaches live off of filth. Terrorists feed off of hate and fear.