Mark Helprin in WSJ

By all means, take Mosul, and continue on until ISIS is no more.

But ISIS, also known as Islamic State, is and has been the wrong focus. Were it not holding hostage the scattered populations it controls in urban areas, a properly directed military coalition of two or three Western powers, or the United States alone, could roll it up in a week. Even as things are, and despite the chaos and cross-loyalties in the present theater of war, with competent diplomacy and military force ISIS could be crushed in a matter of months. The key is NATO’s activation under Article 5 in behalf of alliance member Turkey, which, if only technically, has nonetheless come sufficiently under attack to do so.

With air support from American and French carriers in the Mediterranean, the U.S. Air Force at Incirlik and Gulf bases, and the Turkish, Saudi, and Gulf States air forces, in very short order Turkish divisions from the north could link up with Saudi, Jordanian and an Egyptian expeditionary force from the south, stiffened by American, British, and other NATO units where needed, to cut Syria in half. With Kurds and Iraqis closing from the east, this would simultaneously surround ISIS and confine the Syrian regime in a truncated enclave shielded by its Russian patrons.

The primary purpose of such action, however, would not be to defeat ISIS. Though at the moment ISIS is undeniably the most publicity-rich and barbaric of the jihadist movements, in relation to its structure and resources its ambition to unify the Islamic world has—as in the case of bin Laden, Nasser, and the Mahdi of the Sudan—doomed it from the start. While much has been made of its links to other jihadists in Africa and elsewhere, these alliances have little practical effect, being little more than the distant salutes from one group of psychotics to another. That ISIS has survived for years is less a testament to it than an indictment of the quaking West.

Much more befitting of the power and history of the U.S. and its allies would be to sever and destroy the toxic, threatening bridge that Iran has built from Afghanistan to the Mediterranean, with, astoundingly, the patronage of the president of the United States. Anchored by soon-to-be-nuclear Iran, an integrated politico-religious-military front including Shiite-directed Iraq, Syria and Lebanon will emerge in the near future if current trajectories remain undisturbed.

This entity will have a population almost half that of the United States; the immense oil wealth of Iran and Iraq; ports on the Mediterranean, the Persian Gulf, and Indian Ocean; nuclear weapons; ICBMs; and, until it will no longer need Russia, for which it has no brief, the mischievous and destructive cooperation of Vladimir Putin.

If, under the discipline of an Iran drunk with its successful bamboozling of the West, this power turns its eyes south to Jordan and Saudi Arabia, the Middle East will be entirely transformed. When Iran crosses the nuclear threshold, so will Saudi Arabia. The Shiite population of the Gulf States will be emboldened. Egypt will have to choose appeasement or standing with its Sunni co-religionists. How these elements would sort themselves out cannot be known in advance, but keep in mind that the cultures and governments of the Islamic world are hardly shy about violence and war.

The particular irony here is that during the Cold War the U.S. and Britain created the toothless and ineffective Central Treaty Organization (Cento), known, until 1959 when Iraq dropped out, as the Baghdad Pact. Cento was created to throw the same east-west bar across the Middle East (then including Pakistan) that Iran is in the latter stages of securing. The purpose was to block Soviet expansion southward toward warm-water ports. Despite the efforts of Eisenhower and Dulles, Cento quickly became an alliance just in name.

President Obama has succeeded where they could not, in building that structure—for Iran. For the leading state sponsor of terrorism. For a fanatical nation that in 10 years or less will possess nuclear warheads and ICBMs. For a nation that captures and humiliates our citizens, diplomats and sailors, that supplied the focused charges that killed our soldiers in Iraq, and that chants “Death to America” at the opening of its parliament.

Iran need not fulfill any part of the nuclear agreement it has not even signed and that in the view of our State Department is not legally binding. Even if it were, who knows how the Farsi text might be interpreted? Yet, despite Iran’s violations of United Nations resolutions and its ongoing depredations across the Middle East, we honor and exceed our “obligations,” and shower the Iranians with money, ransom, access, encouragement, and protection. Only the genius of Barack Obama and the cunning of John Kerry (in his presence the Iranians understandably smiled with joy) were capable of achieving this while simultaneously bringing about the reintroduction of Russia into the region, in force—a feat that over 42 years and 10 administrations, Republican and Democrat, no one else was able to accomplish.

Before World War I, the U.S. was focused on Pancho Villa, and sent a much heralded expedition that failed to catch him. But even as he was fading away, he captured the American imagination. All the while, Germany was rising, and because we were unable to see how this would play out, and because some saw Germany as our natural ally, we were blind to it.

Now we are blinded to Iran in favor of ISIS—in its horror and sensationalism the matador’s red cape that distracts from the truly mortal threat, the sword. We know that the Iranians are skillfully using this dynamic. The question is, given Mr. Obama’s seemingly inexplicable yet indefatigable sponsorship of Iran, and his slow-motion approach to ISIS, is he using it as well?