‘Tell me, how does this end?’ asked US general David Petraeus during first push to Baghdad in 2003

The French statesman Georges Clemenceau once said: “War is a series of catastrophes that results in a victory.” In the case of the invasion of Iraq, however, the war that began 20 years ago started in victory and has ended in a series of catastrophes.

The main US military pullout from Iraq was ultimately completed by 2011, finally answering the question posed by Gen David Petraeus during that first push to Baghdad in 2003: “Tell me, how does this end?” Yet the long shadow of the invasion still looms over the international order, staining the reputation of those who instigated it and the political process itself, and dealing a heavy blow to the self-confidence that the west felt in the years after the fall of the Berlin Wall.