Are you feeling lucky?

Don't know about you, but I certainly am. I was due to go to Euston this morning, fortunately for 11 am, if it had been any earlier there's a very good chance I could have been caught up in the situation in London today.
What I persistently fail to understand is why terrorists think that bombing will change the low opinion that most people hold about them. After all, if their arguements are so persuasive let us hear them in democratic debate, surely then, if their case is strong enough then sufficient people who have the power to make changes will agree.
All that these cowardly attacks do is strengthen public opinion against the people who carry out such public outrages, surely the exact opposite of the perpetrators' intentions?
The other question, of course, is how to deal with such individuals, as far as I am concerned they gave up any claim to their own human rights when they denied their victims their rights, yet all this would do is allow them to become political or religious martyrs - which seems to be what they want. Therefore the only action to take with them is to treat them fairly but deny them the oxygen of publicity.