It is often wrongly asserted that Britain created Iraq in the 1920s. In fact, Iraq had long existed as a loose federal unit within the Ottoman empire, consisting of the three provinces of Mosul (mainly Kurdish), Baghdad (Sunni) and Basra (Shia). Britain did, alas, try to create an inappropriately European-style unitary nation state out of this confederation and thereby laid the basis for the centralised tyranny that modern Iraq became. It would be fitting if Britain could now play a role in helping to restore the status quo ante of a looser, federal country based on those three provinces.

There are many obstacles to this "radical federalism" (including, as it happens, Britain) but, as Gareth Stansfield argues inside, it is Iraq's best hope of avoiding long-term conflict. Iraq is already splintering: Basra in the south and Erbil in the north govern with little reference to Baghdad and there are reports of extensive population movements. This need not mean partition—there is a role for a reduced central state. But it does mean accepting reality, and coaxing the Iraqi centralists into accepting it too. Despite the many federal phrases in the new constitution, there is no real agreement between centralists and federalists about the things that matter. If they cannot agree on even a mild federal programme, then Iraq's three main groups will have to agree to disagree and to lessen their claims on one another—acknowledging that 85 years after the British first tried to create one, Iraq still lacks the basis of a European nation state.

What would John Stuart Mill—our greatest ever public intellectual, according to Richard Reeves—have said about Iraq? In "A Few Words on Non-Intervention," he declared that outside intervention against tyranny is rarely justified, because if a people cannot topple their government themselves, they are either not really a people or not ready for liberty. Mill lived before modern totalitarianism, but on Iraq and many other current concerns, he turns out to be surprisingly relevant—and a more challenging liberal than is often assumed.