An Islamic State militant waves a flag in Raqqa, Syria, in 2014. (Stringer/Reuters)

Monday is the 100th anniversary of something called the Sykes-Picot agreement, an occasion that has touched off a small frenzy of Washington think-tank conferences and journal articles — not to mention Islamic State manifestos. Mark Sykes and François Georges Picot were diplomats from Britain and France, respectively, who agreed on a secret plan to partition the collapsing Ottoman Empire. The result, after a few more years of imperialist machinations, was the creation of Iraq, Syria, Jordan and Lebanon — the heart of what is now the bloody chaos of the modern Middle East.

The anniversary has become an occasion for debate about what could or should be made of that mess, once the Islamic State — for which Sykes-Picot has become an unlikely rhetorical touchstone — is militarily defeated. Should Iraq and Syria retain their current borders and centralized political systems, which have the effect of lumping together Sunnis, Shiites, Kurds and smaller ethnic groups that have been at war with each other off and on for centuries? What about Lebanon, whose elaborate power-sharing arrangements have produced a seemingly in­trac­table political gridlock?

Not surprisingly, reasonable people differ on these questions. One broad current of opinion says Iraq and Syria must be preserved as nation-states. The two countries, it is said, were distinct and often competing entities long before Sykes-Picot; their people have developed national allegiances over the past century that transcend sect; and anyway, attempting to redraw the borders would create more problems that it would solve. “There is no way to divide borders and create homogenous states,” writes American Enterprise Institute scholar Michael Rubin. “To even try is to conduct ethnic and sectarian cleansing.”

Another school says it’s folly to suppose that either country can be patched back together. The leaders of Iraqi Kurdistan appear determined to push toward independence, though they differ on whether to do it slowly or quickly. “Iraq is a conceptual failure, compelling peoples with little in common to share an uncertain future,” wrote the head of Kurdistan’s security council, Masrour Barzani, in a recent op-ed in The Post. For its part, the Islamic State has made the erasure of the border between Syria and Iraq — which divides two majority-Sunni regions — one of its central ideological tenets.

Some Arab leaders and thinkers say the West should stay out of this debate — Mr. Sykes and Mr. Picot and their colonializing descendants, up to and including George W. Bush, have done more than enough damage, they say. Others contend the region can be stabilized only by a foreign intervention — not another Western invasion, but maybe a U.N. trusteeship, like those that managed several pieces of postwar Yugoslavia. “The traditional solutions for this region will not work,” argues the Egyptian human rights activist Bahey eldin Hassan. “Some states are not qualified for now for their own people to run the country.”

The Obama administration, for its part, has embraced the “keep out” imperative. Its mind-set is “to define our interests very narrowly and focus very aggressively on achieving those interests,” Obama’s envoy to the region, Brett McGurk, recently told Robin Wright of the New Yorker. In Iraq that has meant investing heavily in the survival of the central government and its weak prime minister, Haider al-Abadi. The hope is that Abadi will provide just enough political cover for the U.S.-led reconstruction of just enough of the Iraqi army to retake Mosul, Iraq’s second-largest city, with the help of the Kurds.

In Syria, Secretary of State John F. Kerry indefatigably pursues the mirage of a “transitional” government that would somehow unite the genocidal Assad regime with its victims. The diplomacy is a fig leaf that Obama uses to rationalize a refusal to support more consequential action to remove Bashar al-Assad while patching together an ad hoc Arab-Kurdish force to advance toward Raqqa, the Islamic State capital.

The problem with this minimalist approach is that it has obstructed the emergence of a genuinely workable consensus about the future of the two countries. Though the U.S.-orchestrated military campaign could, within the next year or so, effectively destroy the Islamic State by recapturing Mosul and Raqqa, there’s no realistic plan for the borders of political structures that would replace it. That, in turn, makes some potential contributors to the offensive, such as the Kurds, reluctant to go forward. Obama’s refusal to engage politically thus makes even his narrow objectives unachievable.

Outside the administration, not many people believe Iraq and Syria can survive in their present form. At a minimum, they will have to become loose federations, like Bosnia after the Yugoslav wars. Who will devise those solutions, and how will they be brought into being? On that, this U.S. president is punting — which means the would-be successors to Sykes and Picot must wait for another year.

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