On October 31, Iraqi government forces finally entered Mosul, the last major stronghold in Iraq occupied by the Islamic State (also known as ISIS). The battle marked a decisive shift in a two-year offensive to erode ISIS’ stubborn hold over swaths of territory in Iraq and Syria. Retaking Iraq’s second-largest city, which ISIS overran in June 2014, would greatly damage the group’s legitimacy, weaken the viability of its so-called caliphate, and cut off its access to the $425 million in currency reserves it stole from the city’s central bank. Now, with the city almost surrounded and Iraqi forces entering its eastern suburbs, Mosul is not far from liberation.

But as U.S. coalition forces begin their advance on Raqqa, the self-declared capital of ISIS’ caliphate in Syria, a far more complex fight awaits them. Unlike in Iraq, where Washington supports the Shiite central government in Baghdad and uses air strikes to back the Shiite militias, in Syria the United States lacks reliable ground forces. Few are currently motivated to fight ISIS. President Bashar al-Assad does not want to destroy the caliphate before it knocks out more moderate rebel fighters in the field, such as elements of the Free Syrian Army around Aleppo, who could be considered alternatives to Assad’s rule. The Syrian government and its Russian allies would prefer the West choose between Assad and ISIS, knowing that it would pick the former. It is no surprise, then, that for months the Russian air campaign in Syria has overwhelmingly targeted anti-Assad rebels rather than ISIS.

The Syrian opposition knows that the United States has no stomach for removing Assad. But for them, Assad and his Russian allies are an immediate, mortal threat to their survival in a way that ISIS, now on the defensive, no longer is. Should ISIS be destroyed, moreover, there is no evidence that the administration of U.S. President Barack Obama would confront Russia over its air strikes or provide the rebels sufficient arms to defend themselves. After all, Washington failed to come to their aid for almost two years after the Syrian civil war began and has not significantly increased its support even with defeat looming in Aleppo.

As a result, U.S. attempts to train Syrians to fight ISIS have netted few results. The rebels, of course, are not a unified group, nor are their patrons. The Islamist Ahrar al-Sham coalition, for example, is supported by Saudi Arabia but shunned by the United States, which favors more moderate groups such as the Free Syrian Army. The United States also opposes al Qaeda’s former affiliate Jabhat al-Nusra, now rebranded as Jabhat Fatah al-Sham. But in Aleppo, these groups are all fighting Assad instead of ISIS.

The only effective anti-ISIS troops in the country are the Syrian Kurds, fighting under the banner of the Syrian Democratic Forces. The Kurds have made real progress and are a major part of the driving force behind the recent offensive toward ISIS’ Syrian capital, Raqqa. But they are also in an extremely vulnerable position. Assad has already stated his intent to retake control of all of Syria, and after the Mosul campaign his Iraqi allies will reach the Syrian Kurds’ eastern border. To the north, Turkey has concentrated its energy on a campaign against both ISIS and the Syrian and Turkish Kurds in Syria. On October 31, Ankara even called for the United States to prevent the Kurds from entering Raqqa, in favor of Turkish-backed forces.

The Kurds’ persistent curse—their lack of a great-power ally—is haunting them once again.

The Kurds’ persistent curse—their lack of a great-power ally—is haunting them once again. Although Russia has been friendly to their cause, there is no evidence Moscow would oppose its client Assad on their behalf. The United States is their only hope, and the presence of U.S. Special Forces among their units should encourage them. But the United States is unlikely to support the Syrian Kurds, who lack the defensible terrain of their Iraqi brethren, against all their enemies—Assad, Iraq, and NATO ally Turkey—over the long run. At some point, surrounded by enemies on three sides, the Syrian Kurds will be forced to look to their own survival. 


The end of ISIS has another unwanted side effect for the region’s Sunnis: it has the potential to rebalance Sunni-Shiite power. Assuming that Assad is able to reestablish control of Syria, Iran, the greatest Shiite power, will have uncontested access to the Mediterranean (by way of two friendly neighbors) for the first time since Xerxes. At the same time, Tehran is finally being unshackled from U.S.-led economic sanctions, which will increase Iran’s power dramatically at the very moment Saudi Arabia’s relationship with the United States is at its lowest ebb in decades. To make matters worse, Russia’s military intervention on behalf of Assad—the first uncontested use of Russian military power in the Middle East in history—has been a powerful object lesson for the region. States are now achieving their ends through Russian, not U.S., power. And Russia is firmly on the side of the Shiite states.

The hard truth for Sunni Arab states is that ISIS’ defeat may strengthen the Iranian coalition. The Sunni states are now in the untenable situation of clinging to a Sunni-dominated regional order that was created by the United States after the 1973 Yom Kippur War and is now in the midst of crumbling. Yom Kippur ended the Arab myth that Soviet arms were an effective tool of policy. After the war, the predominance of U.S. power meant that U.S. solutions, such as the peace process, were on the table, and Sunni states no longer feared Soviet power.

A Yezidi member of the Peshmerga sits in the town of Bashiqa, near Mosul, November 2016.
A Yezidi member of the Peshmerga sits in the town of Bashiqa, near Mosul, November 2016.
Alaa Al-Marjani / Reuters

Today, those Sunni states are again under severe pressure from their regional rivals. Against every one of its economic and geopolitical interests, Saudi Arabia was compelled to cut oil production at the most recent OPEC meeting in September, allowing Iran and Russia to begin earning hard currency again. In an October meeting of the UN Security Council, Egypt unexpectedly abandoned the Arab position on Syria to support Russia, and the two countries recently conducted joint military exercises for the first time in modern memory. The most likely explanation is that Egyptian leaders recognizes Russian power as the decisive force in the region: it actively intervenes, it is reliable, and it does not come with strings about democratic governance attached. It delivers results.

In Turkey, meanwhile, President Recep Tayyip Erdogan has met with Russian President Vladimir Putin three times since June and recently concluded negotiations for a major natural gas pipeline project. It is an unsettling thaw between two centuries-old adversaries. Even Prime Minister Benjamin Netanyahu of Israel, one of the cornerstones of the old order, has begun to hedge. He has traveled to Russia four times over the last year, as it seems that in his calculus, Putin can restrain Iran more reliably than the United States can deter it.

Indeed, the Middle East’s U.S.-backed Sunni order is on the verge of failing. There may be a strong case for replacing that order: the United States’ wars in the region have, after all, been with Sunni jihadists and not with the Shiites, despite an overlap of the two in Iraq. But the consequences of a Shiite-dominated Middle East are unknown and likely vast, affecting everything from oil prices to geopolitics to the Israeli-Palestinian peace process. For at least 25 years, the United States has benefited massively from its ability to dictate those policies by way of its regional allies and clients.

Egyptian leaders recognizes Russian power as the decisive force in the region: it actively intervenes, it is reliable, and it does not come with strings about democratic governance attached.

That is the great difference between a Sunni-dominated Middle East and one ruled by Shiites. In the first scenario, the United States serves as the guarantor of the regional order and can influence that order for its own interests. In the second, the region is controlled by states that do not want or need U.S. help. There is no benefit to the United States of attempting to balance between the two, because the Shiite powers—Iran, Iraq, Hezbollah, and a unified Syria—don’t need U.S. power to force their wishes upon Sunni states, especially if they have the backing of Russia. They will not be vassals of Iran and its allies, but given the daily thousand and one choices of accommodating Iranian wishes versus accommodating American wishes, they will increasingly choose the former.


Once Mosul is liberated, the United States could switch its focus to preventing Shiite hegemony in the region by toppling Assad. But the hour is very late: the opportunity to arm non-jihadist Syrian rebels who could actually change the course of the conflict is long past. The minority Alawite community, from which Assad hails and which constitutes the top leadership of the regime, has no incentive to renegotiate its political pact with Syria’s Sunni majority. Only military pressure could have removed Assad from power, but that pressure has now eased. It is absurd to suggest, as U.S. Secretary of State John Kerry gamely continues to do in Vienna and Lausanne, that Assad should step down now, especially when he is under no military pressure to do so and when he has refused to step down under worse circumstances in years past.

If the United States finds a compelling way to reassure Syrian rebels that it will not let them perish and show the Sunni Arab states that it is still invested in preserving their order, they may in turn show a renewed interest in fighting ISIS. Or the caliphate may collapse on its own—military defeats tend to cascade, and the day after Mosul may turn quickly into the day after Raqqa. But in either case, the United States will finally be drawn feet first into the internecine struggle that is reshaping the institutions of the Middle East. That it happens sooner rather than later is ISIS’ only hope for survival.

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  • ANDREW L. PEEK is Professor at Pepperdine University and a former advisor to the top U.S. and NATO commander in Afghanistan.
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