James F. Jeffrey served as US ambassador to Baghdad from 2010 to 2012, as US ambassador to Turkey from 2008 to 2010 and as Deputy National Security Advisor to George W. Bush from 2007 to 2008.

DW: The Obama administration is having a hard time convincing Iraqis that they should form a unity government. Prime Minister al-Maliki called a unity government that would include Sunni and Shia a "coup against the constitution and the democratic process" and the president of Iraq's Kurdish region, Massoud Barzani, stated that it may be time for Kurdish independence. Is Iraq as a multi-ethnic state on the brink of collapse?

Jim Jeffrey: Not necessarily. I am no fan of al-Maliki, having worked with him for two years. But what he rejected was not what Secretary of State [John] Kerry was selling. In fact, Kerry defended exactly that statement a few hours after al-Maliki made it. Al-Maliki claims that he recognizes that he has to have an inclusive, multi-ethnic, multi-religious government.

But what happened is Iyad Allawi who is his main challenger for many years now came out with a demand for a national emergency unity government, and nobody knew what he was talking about. And al-Maliki quite rightly said, that is not in the constitution.

There is no way al-Maliki can form a government without buy-in from some Sunnis and some Kurds. He can't have an all Shia government because he barely would have enough seats to have a majority in any case given the way the election came out.

And from the standpoint of credibility it wouldn't work. But you are right, the country as a unified whole is hanging by a thread now. The Sunni do not trust al-Maliki, and I do not know if they trust any Shia leader to be fair to them and treat them decently. And the Kurds are moving ever closer to de facto independence.

What would be the consequences be for the broader region?

The best situation would be if we can keep it together, and an inclusive government can reach out to the Sunnis and drive a wedge between most of them and the ISIL [Islamic State in Iraq and the Levant, the ed.] who are a small minority and would become unpopular. That's the best scenario, that's what Kerry and President [Barack] Obama are trying to do.

The worst scenario is the ISIL people push into Shia areas or besiege Baghdad and that pulls in the Iranians which will lead to the Arab states supporting in one way or another the ISIL people or at least the Sunni tribes. Then you would have a regional civil war from the Mediterranean to Iran.

The middle case isn't very good. You would have these three entities in this shell of a country which the ISIL people pushing against the two others and outside powers, Turkey with the Kurds, Iran with the Shia and the Saudis to some degree with the Sunni areas all seeking influence and that's a recipe for conflict too.

A split-up of Iraq is not really in the interest of any of the major actors in the region, the US, Iran, Turkey, Syria and Saudi Arabia. What should they do to stabilize the country?

The problem is it's not in everybody's general interest, but they all have very specific interests. The Turks want a beachhead in Northern Iraq, particularly because of the extraordinary oil and gas riches there.

The Iranians want to support and defend the Iraqi Shia Arabs, but they also want to dominate them because it's a different school of Shia Islam in Najaf in Iraq and they are not happy with Iraq now producing more oil than Iran. And that production is primarily in the Shia south.

And the Sunni Arabs while they see the Sunni as a minority in that one country, see Sunni Arabs as the majority in the region and try to exercise influence with them.

So while everybody has a general interest in the unity of Iraq, the outside powers have a specific interest in supporting their friends. There is nothing that this reminds me of more than, and others have said this as well, the Thirty Years War where, of course, Germany was the object of a dozen outside powers from Sweden to Spain playing with their allies. And look what happened to Germany.

Iraqi Prime Minister al-Maliki's deliberate shunning of Sunnis and Kurds from political power over the past years is viewed as a key trigger for the current crisis. You know and have worked with al-Maliki. Can you describe him and do you think he is capable of changing course?

Every human being is capable of changing. That's what the bible and human experience teaches us. But if there ever was a hard nut to crack it would be al-Maliki. You can do deals with him and we did deals with him all the time in a transactional sense. If we say to him we'll do x if you do y he will do y. He will do what he says.

But to run the kind of liberal, enlightenment system that the constitution is based upon, particularly with the deep ethnic and religious divisions in Iraq, takes a Nelson Mandela or a Vaclav Havel-level leader. And that's not what this guy is.

Washington and probably also Tehran are obviously not very happy with al-Maliki whom they both supported earlier, but there appears to be nobody who could replace him. Do you see some other figure that could unite Iraq or is al-Maliki the least worst choice?

Eight years ago nobody knew about him. He came essentially out of nowhere from the Dawa party and became the consensus candidate. That can happen again. The leader would have to come from the Shia Islamic bodies. I know a number of such leaders, including people close to al-Maliki, his national security adviser Faleh Al Fayad or his former chief of staff Tariq Abdullah.

There are a number of people who have considerable credibility, and then there are also people in the other parties Mr. Abdul-Mahdi, the former vice president of Iraq. There are also some good people among the Shia religious body that I think could be more effective than Mr. Maliki, but they have to get elected by a majority.

The US has been criticized of not being active enough in the Iraq crisis. What's your sense of US policy in Iraq?

Right now it's absolutely on target. The president is ready, he made that clear albeit indirectly, that he will strike if these ISIL guys pose a military threat to our personnel or besiege Baghdad or push into Shia areas. But for him to provide air power and support short of combat troops on the ground he has to see a political solution that he can support with military means.

That's exactly the right approach. The problem is if we don't get that political solution what do we do then with an ISIL presence dominating much of trans-border area between Syria and Iraq. That's a big question.