Kurdish Peshmerga fighters assemble at a shrine on Iraq's Mount Sinjar on Friday, December 19. The Kurdish military said that with the help of coalition airstrikes, it has "cleansed" the area of ISIS militants. ISIS has been advancing in Iraq and Syria as it seeks to create an Islamic caliphate in the region.
Editor's note: Aaron David Miller is a vice president and distinguished scholar at the Woodrow Wilson International Center for Scholars and was a Middle East negotiator in Democratic and Republican administrations. Follow him on Twitter. The opinions expressed in this commentary are solely those of the author.
(CNN) -- We can spend the next few years beating ourselves up and debating the proposition that George W. Bush saved Iraq and Barack Obama lost it. Or we can get real and try to sort out what we can do now to protect U.S. interests in a region that's melting down.
Iraq was never the U.S.'s to win. That point -- along with lowered expectations and focused goals -- must be the basis of any new approach to the region.
And here are three reasons.
1. Demography: There are two factors that nations -- even functional ones (and Iraq is not) -- can't alter: What they are -- their demography; and where they are -- their geography.
Iraq has been dealt an unhappy hand in both departments. There is, to be sure, a sense of Iraq national identity. But at the same time the end of Saddam Hussein's cruel rule -- for which the U.S. is responsible -- opened up a Pandora's box of sectarian tensions and expectations -- for which the U.S. is partly responsible -- that have never been adequately addressed.
In essence, the U.S. overturned a brutal minority Sunni rule and enabled Shia majority rule. The ins became the outs, and the outs the ins. And guess what? Despite several successful elections, $25 billion from the U.S. to train and equip the Iraqi military, and another trillion in support of the Nuri al-Maliki government, Iraq never equitably distributed political and economic power.
Sunnis became disenfranchised, angry and vulnerable to jihadi persuasions; Shia sought to get even, get ahead and maintain a privileged position; and Kurds sought to protect their own interests and effectively create a separate governing authority. Iraq these days isn't so much a nation as it is a collection of battling sectarian groups, each seeking advantage at the expense of the Iraqi state.
2. Geography: Iraq's neighbors, particularly Iran and Saudi Arabia, do not share America's vision of an equitably balanced and independent polity. Each of them has its own vision. Iraq has become a pawn in a regional competition between Sunnis and Shia and Arabs and Persians. Iran wants a weak, stable Iraq not aligned with the West, under Shia influence. The Saudis want al-Maliki out and are happy that the militant group Islamic State in Iraq and Syria may provide that opportunity, even as they fear the jihadists. They want Sunnis empowered and Iran disempowered.
Turkey has made its peace with the Iraqi Kurds and hopes to get them to moderate the radical tendencies of those in Syria, but really has no answer to the ISIS contagion. Jordan is vulnerable to ISIS too, but can't exercise much influence in Iraq.
And that leaves Syria. The regime of Bashar al-Assad is aligned with both Iran and al-Maliki, and -- likely under Tehran's encouragement -- has begun to use military force against ISIS along the Syria-Iraq border. All this regional maneuvering reflects the reality that the neighbors' interests will continue to trump America's by virtue of their proximity, their influence in Iraq, and the reality that Iraq is more vital to them than it is to us.
3. Syria: Iraq can't be stabilized without dealing with Syria. And to date, the U.S. -- by default the only power that remotely has the capacity to alter the course of the civil war there -- has been unable and unwilling to do that. The ISIS threat may prompt a review of the Obama administration's Syria policy, but we should be under no illusions that Washington is ready to jump in with a comprehensive political, economic, and military strategy to end the conflict.
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Indeed, the United States will be faced with some tough choices. It may find itself in the odd position of ramping up support for the more moderate Sunni rebels in Syria but also striking ISIS. That means we will be trying to weaken al-Assad on one hand, but indirectly strengthening him on the other by attacking a common enemy. Under no circumstances should the Obama administration commit to trying to put two broken nations back together again. Bottom line is that the real challenge is ISIS, which is likely to remain ensconced in parts of Syria and Iraq.
What should Obama do?
First let's be clear about what he shouldn't do. The United States needs to abandon any illusions that it can transform or find an easy way out of the situation. It is stuck in a region that it can't fix or leave. There isn't a single problem in this region that has a comprehensive or definitive solution. Instead, the U.S. should accept the reality that it will be dealing with outcomes, not happy endings, there. Iraq may never be a unified polity, but it need not necessarily be a failed one.
The question is, can we shape these outcomes to our advantage? Bush 43 tried to do too much; Obama too little. Is there a balance?
The U.S. needs at least three different but related approaches:
1. Coordinate with regional partners. Sure, in the case of Iran, it's like putting the fox in charge of the chicken coop. But the U.S. can't begin to deal with ISIS on its own. Iran is the key external power in Iraq. And Turkey, Jordan and Saudi Arabia have a stake in stopping ISIS's advances. The U.S. may have to accept the reality that the evil al-Assad is a hedge against ISIS, even though his policies helped to facilitate its rise.
2. Think diplomacy first, then military force. You need the first to make the second effective. That coordination must try to produce a more acceptable political arrangement in Baghdad, with or without al-Maliki. Without the Iraqi government regaining Sunni support, ISIS will continue to roll. And this means some new and more inclusive political arrangement in Baghdad to share power.
Forget democracy and making Iraq whole. To bring Sunnis around and check ISIS, we may have to not only concede influence to Iran but also to some pretty bad Sunnis, including former Saddam supporters and insurgents.
3. The U.S. will need to do what it can to buck up the Iraqi military. This could easily lead to sending additional advisers, but under no circumstances should it involve the use of combat forces. We may well have to use airstrikes and drones against ISIS. And this is tricky, because it risks feeding jihadi sentiment. That's why a new political arrangement is mandatory.
But even without it, the United States must face the reality that ISIS -- with money, passports, and a base of operations -- will emerge as a threat to our friends in the region, to Europe and ultimately to us.
We shouldn't run scared. ISIS's own ideology will produce a counterreaction among Iraqis who will oppose its harsh, unforgiving ideology. Indeed as the International Crisis Group points out, ISIS is its own worst enemy.
The region is littered with the remains of failed jihadi efforts, including al Qaeda central. In 2013, there were 17,800 global fatalities as a result of terrorist attacks. Only 16 of those were Americans.
Terror is not a strategic threat to the homeland right now. But it may well require a coordinated counterterror effort with our regional and international partners to prevent it from becoming one.
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A Peshmerga fighter looks down at the body of an alleged ISIS fighter in Zummar, Iraq, on Thursday, December 18.
A Kurdish fighter stands next to a destroyed armored vehicle in northern Iraq on December 18. The vehicle was destroyed by an improvised explosive device placed by ISIS militants.
Peshmerga fighters stop to check a vehicle in Zummar on December 18 as they continue to battle ISIS fighters near the border with Syria.
Pro-Iraqi government forces guard a shrine in Balad, Iraq, on Monday, December 15.
A Yazidi woman displaced by ISIS militants tends to a fire Wednesday, December 10, at a shelter in Dohuk, Iraq.
A Kurdish child from the Kobani, Syria, area holds laundry at a refugee camp in Suruc, Turkey, on Monday, November 17. Tens of thousands of people have fled Kobani, known in Arabic as Ayn al-Arab, to escape ISIS.
Smoke rises from Kobani following airstrikes on November 17. The United States and several Arab nations have been bombing ISIS targets to take out the group's ability to command, train and resupply its fighters.
A Kurdish child from the Kobani area holds on to a fence at a refugee camp in Suruc on Sunday, November 16.
People in Suruc watch smoke rise near the Syrian border during clashes between ISIS members and armed groups on Thursday, November 13.
A bomb (upper left) falls on an ISIS position in Kobani during an airstrike by the U.S.-led coalition on Saturday, November 8.
Iraqi military forces take up position in Jurf al-Sakhar, Iraq, on November 8.
Fire and smoke rise from Kobani following airstrikes against ISIS on Thursday, October 30.
Iraqi special forces search a house in Jurf al-Sakhar on October 30 after retaking the area from ISIS.
Smoke rises during fighting in Kobani on Monday, October 27.
ISIS militants stand near the site of an airstrike near the Turkey-Syria border on Thursday, October 23.
An explosion rocks Kobani during a reported car-bomb attack by ISIS militants on Monday, October 20.
People watch Kobani from a hill near the Turkey-Syria border on October 20.
Kurdish fighters walk to positions as they fight ISIS forces in Kobani on Sunday, October 19.
A U.S. Air Force plane flies above Kobani on Saturday, October 18.
Heavy smoke rises in Kobani following an airstrike by the U.S.-led coalition on Saturday, October 18.
Cundi Minaz, a female Kurdish fighter, is buried in a cemetery in the southeastern Turkish town of Suruc on Tuesday, October 14. Minaz was reportedly killed during clashes with ISIS militants in nearby Kobani.
Turkish police officers secure a basketball stadium in Suruc on October 14. Some Syrian Kurds have been held there since crossing from Syria into Turkey.
Kiymet Ergun, a Syrian Kurd, celebrates in Mursitpinar, Turkey, after an airstrike by the U.S.-led coalition in Kobani on Monday, October 13.
Smoke rises from Kobani on Sunday, October 12.
Syrian Kurds from Kobani stand outside the grounds of a refugee camp in Suruc on Saturday, October 11.
Alleged ISIS militants stand next to an ISIS flag atop a hill in Kobani on Monday, October 6.
In this photo released by the U.S. Air Force on Saturday, October 4, a U.S. Navy jet is refueled in Iraqi airspace after conducting an airstrike against ISIS militants.
A Kurdish Peshmerga soldier who was wounded in a battle with ISIS is wheeled to the Zakho Emergency Hospital in Duhuk on Tuesday, September 30.
Iraqi Shiite militiamen aim their weapons during clashes with ISIS militants in Jurf al-Sakhar on Sunday, September 28.
Syrian Kurds wait near a border crossing in Suruc as they wait to return to their homes in Kobani on Sunday, September 28.
Syrian Kurds wait behind border fences to cross into Suruc on September 28.
Tomahawk missiles, intended for ISIS targets in Syria, fly above the Persian Gulf after being fired by the USS Philippine Sea in this image released by the U.S. Navy on Tuesday, September 23.
Turkish Kurds clash with Turkish security forces during a protest near Suruc on Monday, September 22. According to 
Syrian Kurds fleeing ISIS militants wait behind a fence in Suruc on Sunday, September 21.
A elderly man is carried after crossing the Syria-Turkey border near Suruc on Saturday, September 20.
A Kurdish Peshmerga fighter launches mortar shells toward ISIS militants in Zummar on Monday, September 15.
An ISIS flag flies on the other side of a bridge at the front line of fighting between ISIS and Kurdish Peshmerga fighters in Rashad, Iraq, on Thursday, September 11.
U.S. Secretary of State John Kerry reads on a flight en route to Iraq on Wednesday, September 10. Kerry traveled to the Mideast to discuss ways to bolster the stability of the new Iraqi government and combat ISIS.
Kurdish Peshmerga fighters fire at ISIS militant positions from their position on the top of Mount Zardak, east of Mosul, Iraq, on Tuesday, September 9.
An Iraqi fighter jet flies over Amerli, Iraq, on September 3. Amerli had been under siege by ISIS militants.
Iraqi volunteer fighters celebrate breaking the Amerli siege on Monday, September 1. ISIS militants had surrounded Amerli, 70 miles north of Baquba, Iraq, since mid-June.
Kurdish Peshmerga forces stand guard at their position in the Omar Khaled village west of Mosul on Sunday, August 24.
Kurdish Peshmergas fight to regain control of the town of Celavle, in Iraq's Diyala province, on August 24.
Peshmerga fighters stand guard at Mosul Dam in northern Iraq on Thursday, August 21. With the help of U.S. military airstrikes, Kurdish and Iraqi forces
Displaced Iraqis receive clothes from a charity at a refugee camp near Feeshkhabour, Iraq, on Tuesday, August 19.
A fighter with Kurdish Peshmerga forces battles ISIS militants near Mosul on Monday, August 18.
Peshmerga fighters inspect the remains of a car that reportedly belonged to ISIS militants and was targeted by a U.S. airstrike in the village of Baqufa, north of Mosul, on August 18.
Kurdish Peshmerga fighters fire at ISIS in Khazair, Iraq, on Thursday, August 14.
Volunteers of the Iraqi Red Crescent Society unload boxes of goods before distributing them August 14 to families who fled from ISIS.
From the flight deck of the USS George H.W. Bush, which is in the Persian Gulf, two U.S. fighter jets take off for a mission in Iraq on Monday, August 11. U.S. President Barack Obama authorized airstrikes against Islamic militants and food drops for Iraqis who are trapped by the militants.
Aziza Hamid, a 15-year-old Iraqi girl, cries for her father while she and some other Yazidi people are flown to safety Monday, August 11, after a dramatic rescue operation at Iraq's Mount Sinjar. A CNN crew was on the flight, which took diapers, milk, water and food to the site where as many as 70,000 people were trapped by ISIS. But only a few of them were able to fly back on the helicopter with the Iraqi Air Force and Kurdish Peshmerga fighters.
Thousands of Yazidis are escorted to safety by Kurdish Peshmerga forces and a People's Protection Unit in Mosul on Saturday, August 9.
Iraqi Shiite volunteers who have joined government forces to fight ISIS take part in a training session near Basra, Iraq, on Thursday, August 7.
Thousands of Yazidi and Christian people flee Mosul on Wednesday, August 6, after the latest wave of ISIS advances.
A Baiji oil refinery burns after an alleged ISIS attack in northern Selahaddin, Iraq, on Thursday, July 31.
A Syrian rebel fighter lies on a stretcher at a makeshift hospital in Douma, Syria, on Wednesday, July 9. He was reportedly injured while fighting ISIS militants.
Iraqis who fled fighting in the cities of Mosul and Tal Afar try to enter a temporary displacement camp in Khazair on Wednesday, July 2.
Peshmerga fighters check cars at the entrance of a temporary displacement camp in Khazair on Thursday, June 26.
Kurdish Peshmerga take their positions behind a wall on the front line of the conflict with ISIS militants in Tuz Khormato, Iraq, on Wednesday, June 25.
Peshmerga fighters clean their weapons at a base in Tuz Khormato on June 25.
New army recruits gather in Najaf, Iraq, on Wednesday, June 18, following a call for Iraqis to take up arms against Islamic militant fighters.
An MH-60R Sea Hawk helicopter lands on the aircraft carrier USS George H.W. Bush in the Persian Gulf on Tuesday, June 17.
Newly recruited Iraqi volunteer fighters take part in a training session in Karbala, Iraq, on June 17.
Members of ISIS prepare to execute soldiers from Iraq's security forces in this image, one of many reportedly posted by the militant group online. CNN cannot independently confirm the authenticity of the images.
Iraqi men chant slogans outside of an army recruiting center to volunteer for military service Thursday, June 12, in Baghdad.
Kurdish Peshmerga forces, along with Iraqi special forces, deploy their troops and armored vehicles outside of Kirkuk, Iraq, on June 12.
Children stand next to a burnt vehicle during clashes between Iraqi security forces and ISIS militants in Mosul on Tuesday, June 10.
Civilians from Mosul escape to a refugee camp near Irbil, Iraq, on June 10.
