Terrorism isn't real. Just a bunch of worthless criminals. Don't get me wrong, I'm not saying its not horrible for people to kill people, nor am I denying that there are people doing horrible things in the world. But calling for war is what they want.
They are about as effective as internet trolls. What makes a troll effective? Engaging it. Talking to it. Building for it a soapbox so that it may shout louder for others to hear. You can't fight an ideology with guns. Take a line from TSA: To fight is to feed it, to punish it is to breed it, madness knows no bridle but the knife. Trouble is, killing someone for an ideology does not kill the ideology, and in fact it validates the cause. You simply make the problem worse.
War creates little else but more war. Look at the US. We've been at war for decades with, well, everything - and what has it got anyone but pain and suffering? The World derides us for being warmongerers, despises us, As they should -
attacking another country for their belief structure, call them terrorists or not, makes you no better than terrorists yourselves.
Its all fear mongering. Terrorism is entirely ineffectual. 13 people died? A tragedy yes, but millions die every day, and it doesn't make news. Give it a news story, and its somehow important. We've now made heroes and martyrs out of every single one of those criminals, which strengthens their ideology, brings them more recruits, makes the problem worse.