Oftentimes when the U.S. superpower intervenes in the business of other nations, after U.S. troops withdraw, the American people lose interest and the country disappears from the consciousness of the public. For example, after the Vietnam War in the 1970s, the exhausted and disgruntled American public no longer cared what happened to the poor, faraway land. That same phenomenon initially occurred with Iraq after Barack Obama withdrew U.S. forces at the end of 2011 from the long American occupation on a schedule set by George W. Bush. However, on the fifth anniversary of Obama’s announcement that the American combat mission had ended, Iraq is still in the news because the brutal group Islamic State (or ISIS) took over about one-third of Iraq—areas where the Sunni Arab Muslim minority live. Not coincidentally, those were the same areas that most violently opposed the U.S. occupation from 2003 to 2011.

The reason the Sunnis fought so hard against the Americans was that for decades they had used central governmental power to control and oppress the other two main groups in the artificial country—the minority Kurdish population in northern Iraq and the majority Shi’ite Arab population in the southern part of the country—and the American invasion had thrown the Sunnis out of power and installed a Shi’ite dominated government that returned the favor. George W. Bush and Barack Obama have been criticized for propping up the chauvinistic and Shi’ite government of Nouri al-Maliki, as he predictably failed to deliver on promises to reintegrate Sunnis into the new army and give them positions in the Iraqi government’s civil service.

Al Qaeda in Iraq, an even more radical affiliate of the main al Qaeda group in Pakistan, which was created to oppose the ill-conceived U.S. invasion, went to Syria and morphed into the even worse ISIS. When the group stormed back into Iraq in 2014 and took over the Sunni third of the country, it found not-so-surprising support from Sunnis, who preferred the even the vicious group’s rule to the oppression of Maliki’s Shi’ite dominated government.

After ISIS’s invasion of Iraq, al-Maliki was thrown out as Iraqi leader, and Hadar al-Abadi, a nominally more inclusive leader, became prime minister. However, recently large protests in the capital of Baghdad have erupted over Iraq’s broken political system, which the Americans installed in 2003. In response, al-Abadi has eliminated some high-level government positions and promised to streamline the government and fight corruption. However, he has also dropped sectarian quotas for hiring personnel in the government, which could further discriminate against and anger Sunnis that are not living in areas of ISIS rule.

The takeover of Sunni areas by the ferocious ISIS is not a good thing, but the long-term effective partition of Iraq into Sunni, Shi’ite, and Kurdish areas might be. For much of its history, Iraq has been an artificial country held together by Sunni strongmen, of which Saddam Hussein was only the last in a long line. After World War I, the British and French carved up the spoils of the losing Ottoman Empire, creating most of the artificial states that have stoked most of the violence in Palestine, Syria, Iraq and Lebanon. To snatch oil, the British combined three provinces of the old Ottoman Empire together, which had more ties to the Ottoman capital in Turkey than they did to each other. Thus, anyone who knew anything about the Middle East—which George W. Bush didn’t bother to consult before carrying out his whim of finishing off Saddam, the Bush family’s mortal enemy—would have predicted that Iraq would be one of the least likely countries in the region to be converted into a stable democratic state. The winner-take-all political culture, the historically severe ethno-sectarian fissures, and the long series of brutal dictators needed to keep a lid on the place were obvious clues that things would not go well for Iraq without a dictator around to hold the pieces together. But none of that stopped curious George from invading a sovereign nation for no convincingly good reason.

In 2009, during the U.S. occupation of Iraq, I published a book called, Partitioning for Peace: An Exit Strategy for Iraq, in which I predicted that because of its ethno-sectarian divides, that country would ultimately be partitioned by peaceful means or by war. I suggested that the United States mediate a voluntary peaceful division of the country into a loose confederation of autonomously governed regions. Unfortunately, that did not happen and the country has been effectively partitioned by war. And there will be more war if this partition is not formalized and the boundaries adjusted.

A formal partition would help at even this late date. During the later years of U.S. occupation, the American military essentially bribed many Sunnis to quit fighting U.S. forces and start fighting the brutal al Qaeda. In the media, this positive outcome and consequent lessening of violence in the country was then cleverly and more "patriotically" portrayed as the fruits of an added American troop surge into the beleaguered land. Yet, in 2005, the United States had had a similar elevated number of forces with no attenuation of violence. Unfortunately, part of the bribe to the Sunnis—promised reintegration into the new Iraqi army and more civil service jobs—was not honored by the Shi’ite al-Maliki government. All the Sunnis got was more oppression from that central government.

Thus, as a result of a "once bitten, twice shy" feeling among Sunnis, this strategy would probably not get them to turn against the even more brutal ISIS today. However, if the existing partition of Iraq were formalized and Sunnis were promised autonomous rule in a loose Iraqi confederation of regions, their incentives might change. No longer needing ISIS to defend against the predations of the Shi’ite central government, Sunnis, knowing that they would rule themselves, might revolt against the barbaric ISIS. This solution is much better than the United States’ recent teaming with Turkey to allow the killing of the only U.S.-friendly people who have to date been effective fighters against ISIS—the Kurds.

As Joe Biden realized before becoming Vice President and loyally keeping quiet, partition is the only workable long-term solution for Iraq and also for generating credible local Sunni forces to fight ISIS—so that large numbers of U.S. forces don’t need to be reinserted into the country.