Anyone up for another regime change in Iraq? It didn’t quite work out the way it was planned last time. Of course, the aftermath of our 2003 invasion of Iraq wasn’t planned at all. At best, there was a wish (“we will, in fact, be greeted as liberators“); at worst, there was the cynical belief that we had to hit someone, and Iraq was an easy target. We don’t need more hindsight to say that Iraq is the worst foreign policy blunder in U.S. history. The Vietnam War killed many more Americans, of course, but Iraq also resulted in terrible loss of life, and perhaps even more gruesome long-term suffering for the injured, given the greater sophistication of battlefield triage. When the United States finally withdrew from Vietnam, chaos and murder did ensue, but, callous as it may sound, the United States was not at risk. In addition to chaos and possibly mass murder in Iraq, we now have a state that has finally failed, after being in intensive care since the British mandate of the 1920s. This failure has brought forth a new and very serious threat to our nation: the Islamic State of Iraq and Syria (ISIS), the cross-boundary force emerging in Iraq. It’s the kind of threat that kills people in their homeland, wrecks buildings and devastates economies.

One can go batty from rage about who is to blame for this dangerous and emerging catastrophe. But, who cares? At no other time since the aftermath of the terrorist attacks of Sept. 11, 2001, has the United States needed more clear-eyed foreign policy judgment. Of course, we didn’t get it then. And now? So far, President Obama has demonstrated a smart understanding of the problem. Obama has stated that simply bolstering Prime Minister Nouri al-Maliki’s government, without new accommodations to Sunnis, is bound to fail. Left unstated, perhaps, is his administration’s belief that we are seeing an extremely dangerous, but necessary, playing-out of Iraq’s uncertain political fate. In other words, and to grossly oversimplify: Iraq’s deep ethnic and religious tensions were stuffed inside Saddam Hussein’s Pandora’s box of dictatorship. The 2003 invasion of Iraq opened the box, and the vapors of violence have been swirling ever since, but this time with a leader who is not only vicious, but incompetent. Hundreds of thousands of U.S. troops could sit on the box, but it never closed, and it never will close until further tragedy plays out and a sustainable new order emerges.

Obama would be wise to put on his realpolitik glasses on when considering his options. How much longevity does ISIS really have? So far, it has taken over regions of the country largely without wealth or oil. It has run over Iraq’s army without a fight; its soldiers see no reason to die for their failing government. But the Shia militia are a different matter, as are the Kurds. As is Iran. ISIS is having its day, but perhaps not for long. In other words, there are others in this mess for whom the threat is more immediate and action more necessary. In the short-term, their interests — the weakening of ISIS — are aligned with ours. For now, we should be cautious, and see whether, for once, others’ interests will result in our dirty work being done for us.