In the 10th anniversary analysis of the invasion of Iraq a lot of the focus will be on what we paid. Lives, dollars, influence and squandered reputation will be totted up against the lack of WMDs and the continuing violence in the rickety state of Iraq.

Naturally enough, our focus is often on our own dead; the Americans and Brits and our two Australians. Even when we do talk about the 100,000 + dead Iraqis, we don’t tend to think much about how they came to be killed. There is a latent assumption that they died in battle as Saddam loyalists or insurgents, or else from mistaken identity or some other direct confrontation with Coalition troops.

This of course is wrong. Of those estimated 100,000 casualties, most have died from Iraqi on Iraqi violence, particularly as the years went on and the tally built. The wave of ethnic and sectarian killing began shortly after the invasion and has continued on till now. It’s likely a wave of bombings will usher in this week’s anniversary.

With four to five thousand civilian deaths occurring every year, Iraq is a manifestly more dangerous place to live than it was under Saddam and even during the invasion. And that doesn’t look like changing any time soon.

It is that continuing violence that is important to recognise as the legacy of the intervention. Whether you agree with the reasons for the 2003 invasion or not, it was the immediate aftermath that was the killing blow to any hope of beneficial change in post-Saddam Iraq.

The post-invasion vacuum

The seeds of disintegration were sown before the first troops had crossed the border. Donald Rumsfeld, the Secretary for Defense, wanted a low-carb operation using as few US personnel as reasonably possible, with most of them to be pulled out within weeks of the campaign’s conclusion.

This meant that the Coalition forces were spread thinly to start with. The old maxim that good soldiers don’t make good policemen proved true and the grunts were struggling to cope with the leaderless country they had inherited. Looting, lawlessness and shattered infrastructure were the backdrop to an Iraq that was starting to come apart.

Then along came L. Paul “Jerry” Bremer and ripped off the scab for good.

Taking over the Coalition Provisional Authority in May 2003, Bremer was chosen precisely because he had no specific experience with the Middle East and no ties to either the US military or intelligence communities. The idea here was that this would make him a free-thinker, unrestricted by doctrine or careerist baggage. That’s a lot like choosing a heart surgeon with absolutely no medical qualifications so that he might be able to “think outside the box”.

The fateful turning point of Bremer’s tenure occurred just days after his arrival. The first fiat issued by the Coalition Provisional Authority banned former members of the Ba'ath Party from holding any public employment. The second decree dissolved the Iraqi army and security services. In true pro-consular style, both of Bremer’s decisions were taken with limited consultation and against the counsel of horrified staff from the State Department and CIA. Only the inner sanctum of neo-cons – Rumsfeld, Cheney and Wolfowitz – were in the loop.

Out with the Ba’ath water

Bremer’s ignorant assumption was that being a member of the Ba'ath Party in Saddam’s Iraq was akin to being a fundamentalist fedayeen. Undoubtedly there were some rusted-on Saddam cronies in the mix, but for ordinary Iraqi public servants, a party membership card was a necessary part of the job. Teachers, for example, got paid about four times more if they belonged to the party, whilst non-members would find their career paths panned out fairly quickly.

Having Ba'aath membership as part of your job didn’t mean you were likely to fight to the death against American troops any more than an Australian primary school teacher being a member of their union would predispose them to throwing Molotov cocktails at the ruling class.

EPA/Mohamed Messara

In two quick strokes, Bremer thus ensured that hundreds of thousands of Iraqis, particularly Sunnis, were thrown out of work and would harbour a permanent grudge against the occupying forces. Nearly half a million ex-soldiers and police were now on the streets, angry and perhaps armed. These were the same security forces who were supposed to be instrumental in stabilising post-invasion Iraq so that coalition troop numbers could be scaled back within a few months.

This resulted in an utter breakdown of Iraqi society. The old order was smashed and no new one in place. No teachers, no state bureaucracy, no security forces except thinly spread Coalition personnel who needed to make sure they were back inside the wire by nightfall. With the social order erased, the population ruptured into tribalism and shocking, yet predictable, violence.

The politics of identity

For patriotic Westerners, it is quite unfathomable that someone might not give a damn about their own country. But in many parts of the world, including the Middle East, the nationality on your passport or birth certificate might not be your primary identity. That you are Iraqi is not important. You probably don’t feel a great deal of pride in that designation because Iraq is just a vehicle for Saddam and whatever kleptocrat replaces him. It is much more crucial to your fate that you are a Sunni Arab from the Shammar clan in Baghdad, or a Shi'ite Kurd from Kermanshah.

With authority gone, Iraqi society resorted to those sub-national identities. And with security and justice seemingly on sabbatical, those who wanted to take the path of violence had no disincentive. Religion, tribe and ethnicity would now determine whose side you were on, where you lived and who you’d vote for.

A rapidly increasing level of ethnic purging began as neighbourhoods were homogenised. This led to a build-up of militias of all types, with Shi'ite groups being funded and trained by Iran and Sunni squads attracting support from Wahabist organisations like al-Qaeda. In our egocentrism we always assume that radical Islamists are out to kill Westerners, but really, the chance to fight their sectarian foes can be just as important and much easier to achieve.

This is why Iraq became a significantly more dangerous (albeit politically freer) place to live post-invasion. Strategies by the occupying forces and provisional rulers to favour different groups to be their right hand men deepened the divide. Meanwhile the scandal of Abu Ghraib and various unlawful killings turned the whole country into a beacon for jihadists.

There is no final tally

The sectarian genie was never put back into the bottle no matter how many troops were temporarily surged into the place. When the rate of killing began to slow it was largely attributable to the fact that the regional cleansing had already been achieved.

This is what Iraq is still living with 10 years on. There are no longer gunships hovering over Sadr City or howitzers pounding Fallujah. But for most citizens life carries an inherent risk. A walk to your mosque for Friday prayers or a car journey through a neighbouring district can still be fatal. When your family members leave home in the morning, can you be sure they will all come home safe that night?

So whilst a decade later we can look at our profit and loss statements and the “final tally” of the occupation, Iraqis will still be paying the bills for years to come.