Twelve years ago, George W Bush gave his "Mission Accomplished" speech from the flight deck of the USS Abraham Lincoln aircraft carrier, confident that the Saddam Hussein regime had been consigned to the dustbin of history, the Taliban regime had been terminated, al-Qaeda was dispersed, if not destroyed, and the desperately needed New American Century was back on track.
That's what he thought. Instead, over the following decade, hundreds of thousands died in the wars in Iraq, Afghanistan and Libya.
War is good for Isis. It relentlessly portrays itself as the defender of Islam under attack from crusader forces as it creates a rigid and determined caliphate, a pernicious world view hated by the overwhelming majority of Muslims - yet appealing to a tiny minority that is still worth proselytising.
Until last spring, IS concentrated primarily on developing and protecting its proto-caliphate. But it has now extended its operations overseas.
This has taken two forms - developing connections with like-minded groups: whether in Libya, Nigeria, the Caucasus, Afghanistan or within the Middle East - and fostering direct attacks on the "crusaders", whether it's the tourists killed at the Bardo Museum and the Sousse resort in Tunisia or, more recently, on the Russian Metrojet, and during the horrific attacks in Paris last weekend.
