In the 1920s, Winston Churchill described Iraq as an ungrateful volcano. President Bush, who keeps a bust of Sir Winston in the Oval Office, probably agrees with Churchill’s description — at least the ungrateful part.

Remembering Churchill also reminds us that Iraq was an artificial British creation stitched together from the ruins of the old Ottoman Empire. Guided by the United States, Iraq’s new leadership faces the same challenge as the one that bedeviled the British from the 1920s to the 1950s: how best to structure the Iraqi political system to prepare that country for democratic self-government.

Iraq has always been difficult to govern. She became progressively more, not less, difficult to govern because external powers found it increasingly difficult to resist interfering in her internal affairs.

Looking to the future, if Iraq is to be remade as a beacon of Islamic democracy, how should the new political system be configured? The introduction of federalism — the division of power between the central and regional governments — may best allow for the true nature of Iraqi society.

Federalism’s principal advantage is that each group has a stake in government and may be able to protect and promote its own interests. But let’s not delude ourselves. By advocating federalism as a solution, we are setting the constitutional bar quite high.

Federalism is a highly sophisticated form of democracy. Successful federalism presupposes the existence of a stable democratic order. The requirements for successful federalism exceed those for successful democracy.

Most importantly, federalism requires populations with a supportive, or at least a congenial, political culture. In Iraq, the ingredients critical to the development of such a political culture are either absent or were diminished by decades of benign or deliberate neglect.

Ethnic nationalism is probably the strongest force working against federalism and, therefore, ethnic federations are the most difficult to sustain. The protracted steps taken recently toward an interim Iraqi constitution laid bare the religious and ethnic fault lines that dominate Iraqi society.

We can’t ignore the fact that the more homogenous a population, the more likely it is to experience non-violent democratization. But violence has always been the currency of governance in Iraq. A cynic might suggest that Iraq’s three major, mutually loathing, groups make the country ungovernable in the absence of a strong leader at the head of a coercive, centralized state.

Successful political reconstruction means striking a new political bargain among the same old groups with conflicting interests and demands that historically have made Iraq a deeply dysfunctional country.

In heterogeneous Iraq, each group has a different notion of what federalism should look like in practice. The Sunni and the more secular Shia want to retain a strongly centralized state. The religious Shia want local autonomy in matters of religion and education but otherwise favor a strong central state.

It is difficult to see how these groups can possibly reintegrate the Kurds back into the state of Iraq. The minimum requirement for the Kurds is a continuance of the status quo, that is, the Kurds won’t settle for anything less than the degree of autonomy they’ve enjoyed since 1992. Given the current absence of political trust among the various groups, the central government that eventually emerges may be completely paralyzed.

Laid out before the new Iraq will be a buffet of constitutional options. No single selection can guarantee a successful system of representative, let alone liberal democratic, government. No one can say definitively which option is more likely to work over the long term. In truth, there are no obviously good constitutional options, only some obviously less bad than others.

It’s highly unlikely that Iraq’s deeply ingrained political divisions can be erased through peaceful, negotiated compromise. All previous efforts to bind together the Sunni and the Shia, while simultaneously accommodating the Kurds, shared one basic characteristic: They all failed.

Today, Iraq appears as ungrateful to some American eyes as it did to Churchill’s 80 years ago. More importantly, President Bush’s blurred vision prevents him from seeing how decidedly volcanic Iraqi politics has remained. At the least, the upcoming year of blazing constitutional conflict should serve to bring reality back into sharp focus.