President Obama’s decision-making about ISIS is dominated by the history of US actions in Iraq, especially his own. It’s this context that determines what he will and won’t do. Getting troops out of Iraq was his promise, that promise is now fulfilled, and it must not be undone. But this is myopic: it is vitally important to see these recent events in the context of a situation that is quite different from the one that has faced us ever since 9/11, because in that context we have a golden opportunity, one that we could only dream of until now.

In late 2001, America faced a frustrating situation. An enemy had declared its intent to destroy us, and had struck a devastating first blow. We had the most powerful military in the world and could easily defeat any power on the battlefield, but this enemy didn’t form up as an army on a battlefield. Our wars have been against states, but this was not a state; it was a loose but extensive network of individuals spread across and hidden among the populations of many countries, including our own. The exasperating result was that while we had a powerful force to defend us, for the most part we couldn’t deploy it. We were able to invade Afghanistan to clean out a sanctuary there, but that was all.

Good intelligence might let us take out a few individuals from time to time, even one as important as Osama bin Laden, but no serious engagement on a field of battle seemed possible. If our enemy ever managed to kill tens of thousands of us by using poison gas in the New York subway, all thoughts would turn to a retaliatory counter-strike, but we would probably have no idea how or where to accomplish that.

If we keep our eyes on this wider context, we can see immediately that what is happening now in Iraq is an absolute game-changer. Our deadly enemy, radical Islam, has taken to the battlefield! At last, they are out in the open, fighting a conventional war as an army and a state. This is the opportunity we could only wish for during the last thirteen years. Jihadis from all over the world are pouring into Iraq to join them, leaving the cover of their surrounding civilian populations and forming up as an army. They are fighting on our terms, on the battlefield, where we are supreme. At last, after years of frustration, we have the chance to engage and crush them.

Deciding to do so should be a no-brainer, but Obama hesitates because he is haunted by the idea of “going back into Iraq.” Determined to avoid doing anything that could appear to undermine what he sees as his achievement, or worse yet look like an admission that he had been wrong, Obama lets his boasts shackle him. And yet there is a simple and convincing answer to all of his hesitation: he is seeing these events in the wrong context. This is about the long struggle between modern civilization and a cruel, barbarous force that wants to destroy it, not about George Bush’s Iraq war. It may be true that Obama¹s premature exit from Iraq led to what ISIS is now doing, but that doesn’t matter. All that matters is that a hitherto elusive enemy is suddenly out in the open on the battlefield.

Obama obviously senses that something is wrong with his stance, and so he commits air power to attack ISIS, all the while claiming that this is only for humanitarian reasons, or for protection of the few Americans who are in the area. And yet it’s clear that he hopes his limited moves will stop ISIS without having to admit that this was his real goal. But in so critical a situation we can't afford self-deception. It is in our national interest to destroy this first organized trans-national jihadi army, and that means bringing  all the resources that we have to the task immediately.

This is the opportunity we have always needed, but never had, to use our overwhelming military superiority against the people who will be the perpetrators of future attacks on the scale of or perhaps worse than 9/11.

And for once, most of the world would cheer us on, because the jihadis’ barbarism and cruelty has soured virtually everyone.

Obama doesn’t see the national interest that is obvious in this wider context because he is fixated on his own interest within the smaller context of Iraq. For their part, the jihadis have evidently calculated that it’s safe for them to take to the field, because Obama will never order American troops to take them down. And in this they are probably right. No wonder they think Allah is with them. If Obama understood the uniqueness of this moment, they might soon think otherwise.

John M Ellis is a Professor Emeritus and former Dean of the Graduate Division at the University of California, Santa Cruz.