Beneath the recent ferment of a highly volatile Middle East lies the region's deepest geopolitical fault line: the decades-long rivalry between Iran and Saudi Arabia. This modern-day contest, rooted in centuries of sectarian enmity, has been best described as the "new Middle East cold war." The U.S. invasion of Iraq in 2003 made that competition a defining feature of the region's geopolitics. It has since been spurred on by the so-called "Arab Spring" and the ensuing civil wars in Yemen and Syria. And as unrest has spread, both sides have supported their sectarian allies, elevating previously local conflicts to zero-sum grudge matches in a series of increasingly dangerous proxy wars.
The current enmity between these two geopolitical rivals is fueled in part by a vacuum left by the United States, which, under President Barack Obama, has pursued a policy of disengagement from the region. Over the past several years, the administration's clear and unambiguous goal has been to unshackle the United States from what it views as costly and painful engagements in a region that offers little hope of reform or meaningful change.
This strategy can be seen in Washington's dithering in Syria, and in the collapse of America's negotiating positions in the nuclear accord signed with Iran last year. But the end result, much to the chagrin of Saudi Arabia and the other Gulf Arab states, has been an undeniable boost to Iranian power, both hard and soft.
A RISING IRAN... AND A SUNNI RESPONSE
Assessments, such as that of veteran Iranian diplomat Sadegh Kharrazi, neatly encapsulate the fears of Sunni governments across the region. As Kharrazi described the nuclear talks: "Iran is now at its peak of power in centuries. Iran's sphere of influence stretches from the Mediterranean to the Indian peninsula, from Kazakhstan to Yemen. This is why the world superpowers have been negotiating with us for so long, that's why we were able to reach a deal which guarantees our interests." This resonates among the Sunni Gulf states, which have since felt compelled to take a more assertive role in defending their interests. The result has been an inflammation of sectarian tensions across the Arab world.
Over the past year, the regional contest stemming from the rise of Iran has assumed new and dangerous dimensions. In what were once wars by proxy, Saudi and Iranian troops are now directly engaged in combat – albeit in separate theaters. Both parties have suffered mounting losses, attesting to the depth of their involvement and providing some truth to the charges that Saudi Arabia is "occupying" Yemen and Iran is "occupying Arab lands" in Syria.
In the former case, Riyadh has long regarded the Houthi rebels, the Shi'a group waging an insurgency against the Yemeni government, as an Iranian proxy seeking to exploit the soft underbelly of the Saudi Kingdom. To support this assessment, the Saudis point to the spike in Iranian weapons entering the country, and to statements by Iran's Revolutionary Guards Corps (IRGC) comparing the Houthis to Iran's longtime client Hezbollah in Lebanon. Late in 2014, alarm in Riyadh reached new heights after the Houthis broke out of their strongholds in the northwest and seized the capital of Sana'a, eventually forcing the Saudi-backed president, Abd Rabbuh Mansur Hadi, into exile. This prompted Saudi Arabia to forge a coalition of nine Arab states and lead it into a war against the rebels. The resulting conflict has inflicted severe damage on the Houthis, but there have also been scores of painful combat losses on the Gulf states, including more than 50 soldiers killed on a single day.
Concurrently, Iran finds itself in an analogous position of defending a Shi'ite ally against an armed Sunni rebellion. Since the outbreak of the Syrian civil war in March 2011, Iran has been providing its longtime ally and proxy, the regime of President Bashar al-Assad, with financial and military assistance, including the deployment of Afghan, Pakistani, and Lebanese Shi'a militias to augment the depleted ranks of his army. Its most capable proxy, Hezbollah, has taken on a prominent role in fighting the Syrian opposition, sending an estimated 8,000 troops next door with some 1,000 (perhaps more) returning in body bags. Despite these losses, it remains committed to the end. As Sheikh Nabil Qawooq, the head of Hezbollah's Executive Committee, has underscored: "We insist on defeating the terrorists and gaining victory against the takfiri plots... because if Syria turns into a center or passage for [the Islamic State] and other terrorist groups, they will not show mercy to Lebanon either."
This support has been countered in kind by the Sunni countries, which see a rare opportunity to go on the offensive and dislodge Iran's oldest ally in the Arab world. Accordingly, they have funded and armed the thousands of foreign fighters who have streamed across Turkey's southeastern frontier to join the fight. In turn, as Syria has descended deeper into a civil war, the Gulf states have taken this support to another level, providing rebel groups with lethal weaponry, such as the highly effective American-made TOW antitank missiles, and forged new powerful rebel coalitions.
These efforts have proven relatively successful. By mid-2015, the Assad regime had lost control over 83 percent of its territory, retreating to its coastal enclave, which is surrounded on all sides by hostile forces. As was the case with Saudi Arabia after the Houthi offensive in Yemen, a sense of panic jolted Tehran to take more decisive action. In late July, with the ink barely dry on the nuclear deal, IRGC Qods Force Major General Qassem Soleimani flew to Moscow to coordinate a joint intervention to rescue Assad. Weeks later, hundreds of IRGC ground troops began arriving in the country. Under the cover of Russian air support and backed by allied Shi'a militias, Iran helped the Syrian Arab Army launch a counteroffensive in rebel-held areas in Homs and Aleppo to the north of Assad's stronghold. Though Iran has insisted its troops are only "military advisers," the high rate of casualties – approaching one soldier killed per day – makes it clear that this is now Iran's war.
Increasingly frustrated by Tehran's success on the battlefield, the Gulf Cooperation Council took the unprecedented step in February of designating Hezbollah a terrorist organization. This followed Saudi Arabia's decision to impose sanctions on several Hezbollah entities last November. For his part, Hezbollah Secretary General Hassan Nasrallah now lists the Saudi leadership alongside its traditional enemies of Israel and the United States. His supporters accordingly added the chant "Death to the Saud family" to their repertoire during the Shiite holiday of Ashura.
In the latest indication that Saudi Arabia is losing ground in this regional contest, Riyadh appears to have walked away from the country that had long served as a battleground between the two powers. In 2005, Saudi Arabia had been an early supporter of the March 14 coalition and its Sunni political movement against Hezbollah and Syrian influence in Lebanon. But in February 2016, Saudi Arabia decided to punish Lebanon for not condemning the attack on the Saudi embassy in Tehran the previous month. Riyadh announced it was stopping payment on $4 billion worth of military aid and other support to the Lebanese Armed Forces, effectively ceding the coastal state to Iranian influence. Referencing the many conflicts in which Saudi Arabia is now engaged, one diplomat explained that Lebanon was "just not a priority anymore."
The escalating Sunni-Shi'ite proxy war has also destabilized the region in another way: by facilitating the rise of the Islamic State (IS) and fomenting an intra-Sunni war. Whereas various Shi'a groups have progressively united behind Iranian leadership, the Sunnis have splintered. Indeed, the jihadi groups spawned by the chaos generated by IS activity are at odds with the Saudi Kingdom, in part because of its overt alliance with the United States, even though the Saudis have in the recent past served as patrons to similar movements. In the last year, IS has made the kingdom a target of its terrorist activities (most conspicuously, by attacking Shi'ite mosques in Saudi Arabia as a means to enrage the population of the oil-rich eastern province to destabilize the Saudi monarchy). The Saudis thus find themselves in the unenviable position of simultaneously opposing their strategic foe, Iran, and confronting more immediate security threats from within their own sectarian camp.
Meanwhile, the meteoric rise of IS in Iraq and Syria has led to deeper Iranian entrenchment in those countries. As the Islamic State conquers swaths of Iraq, Baghdad has grown even more dependent on Tehran for its security, especially because the Obama administration has made clear that it will not commit extensive deployments in order to recover Iraqi territory. This has led Baghdad to lean on the Iranian-backed Shi'ite militias, which have filled the security void left by the retreating Iraqi army. Yet the abuses committed by these Shi'ite militias, organized under the "Popular Mobilization Forces," have the effect of further radicalizing the Sunni populations they encounter, thereby increasing the appeal of extremist Sunni groups that purport to fight for their interests. This vicious cycle thus strengthens both the Shi'a and radical Sunni enemies of the Sunni states, intensifying the violence across the region.
MORE TO COME
Given the flagging American leadership, surging Iranian influence, and expanding Saudi engagements under King Salman, a protracted battle between Saudi Arabia and Iran seems inevitable. But the longer Iran and Saudi Arabia jostle for dominance in the region, the deeper they will be pulled into local conflicts, as they already have in Syria and Yemen, and the more they will find sectarian violence visited upon them and their allies.
The events of the past year demonstrate that the Sunni-Shiite proxy war is not just escalating. It is entering a new phase, the dangers of which we are only beginning to understand.