I wouldn’t underestimate the absence of logic, the sheer depraved thrill of a triumphant cult reveling in its barbarism. But I wouldn’t overestimate it either.

You don’t overrun much of Syria and Iraq without having deployed keen tactical and strategic reasoning.So what’s the objective? To destabilize Jordan by drawing it deeply into the conflict.

At first glance, this seems to make no sense. The savage execution has mobilized Jordan against the Islamic State and given it solidarity and unity of purpose. Yes, for now. But what about six months hence? Solidarity and purpose fade quickly. Think about how post-9/11 American fervor dissipated over the years of inconclusive conflict, yielding the war fatigue of today. Or how the beheading of U.S. journalists galvanized the country against the Islamic State, yet less than five months later, the frustrating nature of that fight is creating divisions at home.

Jordan is a more vulnerable target because, unlike the U.S., it can be destabilized. For nearly a century Jordan has been a miracle of stability — an artificial geographic creation led by a British-imposed monarchy, it has enjoyed relative domestic peace and successful political transitions with just four rulers over four generations.