The Wall Street Journal reports: In the brutal calculation of Middle East politics, the baseline for friendship has always been simple: The enemy of my enemy is my friend.

By that standard, the Islamic State extremist group is creating friendships aplenty. An odd set of bedfellows or potential bedfellows, transcending geographical, ideological and alliance bounds, is emerging from the ranks of those threatened by what many see as the most dangerous militant movement in a generation.

Shiite Muslim Iran and Sunni Muslim Saudi Arabia, for instance, have been bitter foes since at least 1979, when the Iranian revolutionary government of Ayatollah Ruhollah Khomeini hoped to inspire similar revolutions in the Sunni world. But both countries now fear Islamic State’s armed radical Islamist movement, which seeks to usurp their own claimed leadership of the Muslim world.

That led Iran and Saudi Arabia to independently back the same candidate to lead Iraq, in a push for a new government that might unite Sunnis and Shiites to battle Islamic State. This week, Iranian and Saudi diplomats held a rare meeting to consult.

Turkey has long distrusted and worked against ethnic Kurds, especially a violent splinter group known as the PKK that operates out of the mountainous environs of northern Iraq. But the Turks looked the other way when Syrian Kurdish militias affiliated with the PKK played a starring role in the rescue from Islamic State fighters of thousands of Yazidis stranded on a mountainside.

Russia and the U.S. are at loggerheads in Ukraine and elsewhere, including the Middle East. But they agree that the sort of violent Islam practiced by Islamic State, which now controls large swaths of Iraq and Syria, endangers the global order in which both countries compete for influence.

Islamic State even has had a falling out with al Qaeda, the group that spawned it. Al Qaeda’s official Syrian branch, known as the Nusra Front, is outflanked and mocked by Islamic State. So Nusra has joined the fight against Islamic State, clashing violently on the battlefields of Syria.

These countries and movements may be at odds over nearly everything else, but nothing focuses the mind like a mortal threat, say some analysts and former top security officials. Given not only Islamic State’s savagery but its potential to overthrow regimes and spill over borders, they all seem to agree on only one thing: It needs to be stopped.

Lacking a coalition of the willing, the Obama administration should muster up a sort of alliance of the unwilling, these analysts argue. Whether that is possible, and whether the U.S. has the guile and clout to unite such disparate forces—either formally, or more likely in a combination of overt, covert and arm’s-length arrangements—is an open question.

“It has to be patched together, somewhat ad hoc, with maybe some sort of informal and even clandestine agreements on who does what,” says Zbigniew Brzezinski, a former U.S. national-security adviser.

In a region where states such as Iraq and Syria are literally fragmenting, Mr. Brzezinski urges an approach focused on the handful of what he categorizes as truly “viable” states — Turkey, Iran, Egypt, Israel and Saudi Arabia — to confront Islamic State, which also is known by the acronyms ISIS and ISIL. [Continue reading…]