Nir Rosen - who speaks Arabic and has Middle Eastern looks - went to Iraq in April 2003, just days after Baghdad fell.

Entering mosques and tribal meeting halls, and afforded access to fighters' secret meetings and Iraqi homes, he documented the deadly behind-the-scenes manoeuvring in the post-Saddam power vacuum.

The freelance journalist's writings have appeared in The New Yorker, The New York Times Magazine, and Time, among other publications. He is also a fellow at the New America Foundation.

Aljazeera.net: Let's start with the title of your book. What is the green bird?

Rosen: When I was in Falluja, and other parts of Iraq where the resistance was very strong, you would often hear this quote in mosques, or see it in resistance propaganda - that the martyrs were in paradise.

You often saw or heard the statement that the martyrs die with a smile on their faces, die with smelling sweet and the martyrs went to paradise in the bellies of the green bird.

To write your book, you gained access to both Sunni and Shia resistance more than any other American reporter. How did you do that?

I have a very good smile (he laughs). I definitely had more access than many other people. Some of it was because I am Middle Eastern; my father is Iranian.

I looked like everybody else which I think is an important advantage because you get to places more easily. People don't notice you.

I think it's mainly having the right friends. Friends from the right Sunni tribes, friends from the right Shia neighbourhoods who could introduce me to the right people. You need somebody from the right tribe, from the right neighbourhood, from the right sect. More and more, that's what determines whether you can survive.

Has al-Zarqawi's death impacted the insurgency?

I think it's insignificant. I don't think he was so important in the first place.

If anything, he was sort of an advertisement. He came into Iraq to kill infidels and the Shia, become a martyr and go to paradise. He succeeded.

The Americans created Zarqawi, sort of the Zarqawi myth. Right at the beginning, they refused to accept the fact that the Iraqis had liberated or supported popular resistance so they had to blame everything around foreign fighters for the sake of the American [public].

So it seemed for a while like every suicide car bombs was been blamed on Zarqawi. And I just think that created a myth throughout the Arab world. It only helped his cause.

Osama Bin laden recently warned in an internet message Iraqi Shia of retaliation if they continued to attack Sunnis. How seriously should we take his warning?

I don't think Osama bin laden matters much either. First of all, Iraqi Shia are being killed every day anyway.

Every day by the end of 2003, they were being slaughtered on the streets by the resistance and of course by Zarqawi. But I don't think Osama bin laden commands any fighters. He is hiding in some cave somewhere in Pakistan issuing these statements, trying to sound important but he is not the leader of anybody anymore. So it's kind of ridiculous.

I didn't see anyone in Iraq take Osama bin laden seriously. It's definitely true that Shia are resented because they are perceived as the beneficiaries of the occupation. And in many ways, they are in charge now; they control Iraq so everything has been reversed.

In a recent article, you wrote "The occupation has been one vast extended crime against the Iraqi people and most of it has occurred unnoticed by the American people and the media". Can you explain?

Well Abu Ghraib, Haditha, these are the kind of things that get attention. These are only two incidents so they make them seem like the crimes are exceptions.

In fact the occupation is a daily crime, it is little Abu Ghraibs, little Hadithas, being forced to do what the Americans tell you to do. Having American machine guns pointed at you everywhere, having American security convoys shoot at you when you're off the streets, having American tanks block off your roads, American concrete barriers block off your city, American helicopters fly over your house, American soldiers break into your house and raids.

So many little acts and so many innocent Iraqis killed or arrested or humiliated or terrified. Probably hundreds of thousands have been traumatised by this, especially children.

I was "embedded" for two weeks of my entire time in Iraq but for me that was the most traumatic experience that I had in Iraq.

Normally, if I'm on the streets and I see someone pushing an old lady or bullying a child, I'd want to interfere. But here I was with soldiers and they were doing the same thing with Iraqis. I would just stand there and watch and not get involved. And Iraqis looking at me thinking I was some Iraqi collaborator and it made me feel even worse.

In a recent Washington post/ABC News poll, nearly half of all Americans support a timetable for withdrawal. Do you support a withdrawal?

I supported a withdrawal certainly until 2005. In my articles, I was saying that an American withdrawal would prevent a civil war from happening and would force Sunnis and Shia to step up and take responsibility and to co-operate. And it would allow Sunnis to participate in the government.

But now that I think the civil war is sort of open and intense, I don't think an American withdrawal would make much difference and it's possible that an American withdrawal would actually make things worse because there will be nobody patrolling the borders and would allow even more foreign fighters to come into the Sunni areas.

It would allow greater intervention from Iraq's neighbours which will only increase the civil war. I think the Americans should leave. The Americans shouldn't be here occupying Iraq and killing Iraqis but an American withdrawal wouldn't make things better at this point because of the civil war.

In your book, you say that Iraq has been in a state of civil war shortly after the fall of Saddam Hussein's government. How bleak is the future of Iraq?

It's more difficult for me to feel more optimistic because as a journalist on the ground you see the bloodshed every day. You hear about people getting killed, people telling you about their neighbours getting killed; it seems like short-term there is no hope because I think things still have to get much worse before they might get better. The process of ethnic cleansing is only beginning.

I think all mixed areas of Iraq are going to be unmixed, are going to be cleansed like Bosnia before this ends. So there's still a lot left to go. I think Sunnis and Shia hatred at this point in Iraq are so intense that they are beyond the point of reconciliation and the fact that the Shia are so confident because they control the army and the police. I think you're going to see sectarianism spreading to the whole region.

Do you think Iraq should be split into three semi-autonomous provinces?

The Kurds certainly want independence. They don't feel Iraqi, they don't speak Arabic, they don't want to belong to Iraq.

When you ask them about the Iraqi flag, they tell you it is a symbol of their pain. I've never heard a Kurd express any desire to belong to Iraq. And they have virtual independence anyway so it's only a question of time for the Kurds.

But regarding the rest of Iraq, it's much more complicated because the Sunnis don't want to have some form autonomous province. They want all of Iraq just like the Shia want all of Iraq.

Everybody wants Baghdad. Sunnis of course want the oil and the Sunnis are so mixed that even if you divide it into autonomous provinces what would you do with Baghdad and Kirkuk?  It would just be as bloody because most of the bloodshed is happening in mixed areas. So there's no solution at this point I think.

How will the war in Iraq impact the Middle East in the long term?

The idea of a nation might be less important because you have Sunni Arab tribes in Iraq who have relatives in Syria, Jordan and Saudi Arabia and for them borders were never an issue in the first place.

Once the people start really being victimised by the Shia, you'll see their relatives coming in larger numbers to give them more support.

I just don't believe that the Arab world is prepared to tolerate an aggressive Shia Iraq. We've heard statements from Saudi leaders, Jordanians and even from [Egyptian President Hosni} Mubarak warning about the Shia threat. I don't think you will see a Shia Iraq, the situation is only going to get worse.

How has the war in Iraq affected you personally?

My journalistic career began at the age of 26 when I got to Iraq. I'd never been a journalist before. So everything I've learned in the past three years was from Iraq.

In some sense, it has made me an angry person. When I go back to the United States, I feel angry because people don't know how terrible the situation is.

Is the media to blame?

A little bit. They are too slow to expose America's crimes and they still are. I mean I was embedded for two weeks and I saw so many horrible things happen. There are journalists who have been embedded for months, for much of the occupation on and off, and they must have seen things much worse than what I saw.

And not to write about them and glorify the hometown heroes from the US is in itself collaborating with the crime.