Wars
The Iraq War: Why the Invasion Succeeded and the Occupation Did Not
The Iraq War contains two military stories that are almost unrelated. The first is a conventional campaign that defeated a state army in about three weeks and is a textbook illustration of what a modern combined-arms force can do. The second is an eight-year effort to produce a stable country, conducted by the same force, and its difficulty had very little to do with the capabilities the first campaign demonstrated.
The invasion
The conventional phase was fast and one-sided. Air superiority was immediate; the advance moved on several axes; night operations and precision engagement gave a decisive advantage; organised resistance collapsed within weeks. The hardest early fighting came at Nasiriyah from 23 March 2003, where the Marines of Task Force Tarawa fought for the bridges over the Euphrates and the Saddam Canal after an Army maintenance convoy had been ambushed in the town.
Nothing about this outcome is puzzling. It was the war the force had been designed, equipped and trained for, fought against an army weakened by more than a decade of sanctions and air enforcement and organised conventionally enough to be engaged on those terms.
The gap
What followed is the substance of the war, and the transition is where the difficulty concentrated.
The force that arrived was sized and configured to defeat an army, not to secure a country of that population and area. In the first weeks widespread looting went largely unchecked: a period that established, publicly and quickly, that order was not being enforced. That impression is extremely difficult to reverse once formed.
Two early decisions compounded it. The existing army was dissolved as opposed to reconstituted, which removed the institution best placed to provide security and simultaneously created a large body of unemployed men with military training. The senior civil administration was removed on political grounds, which stripped the ministries of the people who knew how to operate them. Both decisions had arguments behind them; both are now generally treated as having raised the cost of everything that followed.
The insurgency, and why it was hard to fight
The opposition that emerged was not a single organisation. It included former regime elements, local groups fighting occupation, foreign fighters pursuing a different agenda (among them the network of Abu Musab al-Zarqawi, which became al-Qaeda in Iraq), and militias contesting power with each other as much as with the occupying force. There was no structure to defeat and no authority to negotiate a settlement with.
The tactical problem was the roadside explosive device, which imposed a continuous cost on movement and drove an enormous protected-vehicle procurement effort. The strategic problem was that operations conducted from large consolidated bases could clear an area and not hold it: forces returned to base, and the area reverted.
By 2006 the violence had substantially become sectarian, with the occupying force positioned between communities instead of against a single opponent.
The 2007 change
The change in approach was doctrinal before it was numerical, though it involved both. Forces moved off the large bases and lived among the population in small outposts, permanently. Protecting civilians replaced pursuing insurgents as the organising objective. Troop numbers were increased.
Running in parallel (and, in most assessments, at least as important) local groups in several provinces, beginning with the Sunni tribes of Anbar around Ramadi, chose to turn against the most extreme factions and were supported in doing so. The security improvement over the following two years was real and substantial.
What it did not produce was a durable political settlement. The improvement in security created the conditions for one; the politics did not resolve, and the withdrawal completed in 2011 left unresolved the questions the war had been unable to answer.
What the institution took from it
Counterinsurgency doctrine was rewritten and moved to the centre of professional education for roughly a decade. Protected mobility, intelligence fusion at low tactical levels, and the integration of civilian expertise into military operations all advanced sharply.
The larger lesson is the one the professional literature keeps returning to: military capability sufficient to defeat an army is not related to the capability required to produce a functioning state, and planning for the first while assuming the second is where the cost of this war was incurred.
Questions and answers
Why did the conventional campaign succeed so quickly?
Because it was the kind of war the force had been built and trained for, against an army that had been degraded by a decade of sanctions and no-fly enforcement and was organised in a way that suited its opponent's strengths. Speed, air superiority, night operations and precision produced a rapid collapse of organised resistance, and the campaign's success is not in dispute.
What made the occupation so much harder?
Several decisions compounded: the force deployed was sized for the invasion instead of for securing a country, the existing army and civil administration were dissolved instead of reconstituted, and there was no agreed plan for what would govern in the interval. Widespread looting in the first weeks established that order was not being enforced, which is very difficult to reverse.
What did the 2007 change in approach consist of?
A shift from consolidating forces on large bases to stationing them among the population continuously, combined with an increase in troop numbers, a doctrinal reorientation toward protecting civilians instead of pursuing insurgents, and (decisive in the outcome) accommodation with local groups who chose to turn against the most extreme factions. The security improvement was real, and how much each element contributed is still argued.
How is the war assessed now?
The tactical and operational competence displayed is generally acknowledged, as is the failure of the political result to justify the cost. The professional literature treats it mainly as a case study in the difference between defeating an army and producing a stable political outcome, and in the cost of planning for the first while assuming the second.