An expert's point of view on a current event.

The Syrian Spillover

Is anyone prepared for the unintended consequences of the war for Syria?

By , a senior fellow at the American Enterprise Institute.

The Syrian civil war has gone from bad to worse, with casualties mounting and horrors multiplying. Civil wars like Syria's are obviously tragedies for the countries they consume, but they can also be catastrophes for their neighbors. Long-lasting and bloody civil wars often overflow their borders, spreading war and misery.

The Syrian civil war has gone from bad to worse, with casualties mounting and horrors multiplying. Civil wars like Syria’s are obviously tragedies for the countries they consume, but they can also be catastrophes for their neighbors. Long-lasting and bloody civil wars often overflow their borders, spreading war and misery.

In 2006, as Iraq spiraled downward into the depths of intercommunal carnage, we conducted a study of spillover from recent civil wars in the Balkans, the Middle East, Africa, and elsewhere in order to identify patterns in how conflicts spread across borders. Since then, Iraq itself, along with Afghanistan, Libya, and Yemen, have furnished additional examples of how dangerous spillover can be. For instance, weapons from Libya have empowered fighters in Mali who have seized large swathes of that country, while al Qaeda-linked terrorists exploiting the chaos in Yemen launched nearly successful terrorist attacks on the United States.

Spillover is once again in the news as the conflict in Syria evinces the same dangerous patterns. Thousands of refugees are streaming across the border into Turkey as Ankara looks warily at Kurdish groups using Northern Syria for safe haven. Growing refugee communities are causing strain in Jordan and Lebanon. Meanwhile, the capture of 48 Iranians, who may be paramilitary specialists, could pull Tehran further into the conflict. Israel eyes developments in Syria warily, remembering repeated wars and concern over the country’s massive chemical weapons arsenal. For the United States, these developments are particularly important because spillover from the civil war could threaten America’s vital interests far more than a war contained within Syria’s borders.

Of course, much will depend on how exactly this spillover plays out — and certainly no one yet knows what will happen in the wildly unpredictable war for control of Syria. But if past informs present, the intensity of the war effect typically correlates strongly to the intensity of the spillover, often with devastating consequences. At their worst, civil wars in one country can cause civil wars in neighboring states or can metastasize into regional war. And it’s the severity of the spillover that should dictate the appropriate response.

There are five archetypal patterns of spillover from civil wars.

Refugees: Spillover often starts with refugees. Whenever there is conflict, civilians flee to safety. The sad truth about civil wars is that often civilians are targets: Without clear front lines and when "enemy combatants" can be any young male who can pick up a gun, the danger is clear. So the goal of the warring armies is often to kill as many of the other side’s civilians as possible or at least drive them from their homes. To avoid the rapine and economic devastation that accompany these kinds of conflicts, whole communities often flee to a foreign country or become displaced within their borders, as more than a million Syrians have.

In addition to their own misery, refugees can create serious — even devastating — problems for the nations hosting them. The plight of Palestinian refugees and their impact on Egypt, Jordan, Lebanon, and Syria since 1948 is a case in point, contributing to instability in their host countries, international terrorism, and wars between Israel and its neighbors.

Beyond this, refugees can often become carriers of conflict. Angry and demoralized refugee populations represent ideal recruitment pools for the warring armies; the Taliban have drawn from angry young Afghan refugees raised in Pakistan, offering them a chance for vengeance and power. Indeed, refugee camps frequently become bases to rest, plan, and stage combat operations back into the country from which the refugees fled. For instance, the camps set up in the Democratic Republic of Congo after Rwanda’s genocide quickly became a base of operations for fleeing Hutu rebels to regroup.

Terrorism: Many civil wars have become breeding grounds for particularly noxious terrorist groups, while others have created hospitable sanctuaries for existing groups to train, recruit, and mount operations — at times against foes entirely unconnected to the war itself. The Palestine Liberation Organization, Hezbollah, the Tamil Tigers, and al Qaeda, to name only a few, all trace their origins to intercommunal wars.

Today, after years of punishing U.S. drone strikes in Pakistan, al Qaeda’a core is weak, but its offshoots remain strong in countries wracked by internal conflict such as Yemen and Somalia. The most recent flare-up is in Mali, where fighters fleeing Muammar al-Qaddafi’s Libya fled with arms looted from his arsenals, and have seized parts of Mali, in some areas even imposing a draconian form of Islamic law. While there had been intermittent rebellions in Northern Mali for years, the civil war in Libya vastly increased the capability of the rebels and created a worse terrorism problem for the region, andpotentially for the world.

These terrorist groups rarely remain confined by the country’s borders. Some will nest among refugee populations, launching attacks back into the country in civil war, and inviting attack against the refugee populations hosting them. In other cases, terrorists may decide that neighboring regimes or a segment of a neighboring society are aiding their adversaries and attack them to try to scare them into stopping their assistance.

Terrorists often start by flowing toward civil wars, but later begin flowing away from them. Jihadists first went to Afghanistan to fight in that civil war in the 1980s but by the 1990s began using it as a base to launch attacks against other countries — including, of course, the United States on 9/11.

Secessionism: As the Balkan countries demonstrated in the 1990s, seemingly triumphant secessionist bids can set off a domino effect. Slovenia’s declaration of independence inspired Croatia, which prompted Bosnia to do the same, which encouraged Macedonia, and then Kosovo. Strife and conflict followed all of these declarations.

Sometimes it is the desire of one subgroup within a state to break away that triggers the civil war in the first place. In other cases, different groups vie for control of the state, but as the fighting drags on, one or more groups may decide that their only recourse is to secede. At times, a minority comfortable under the old regime may fear discrimination from a new government. The South Ossetians, for example, accepted Russian rule but rebelled when Georgia broke off from the Soviet Union, as they feared they would face discrimination in the new Georgian state. After Russia helped South Ossetia defeat the Georgian forces that tried to re-conquer the area in 1991-1992, the next domino fell when ethnic Abkhaz also rebelled and created their own independent area in 1991-1992. The frozen conflict that resulted from this civil war finally burst into an international shooting war between Georgia and Russia in August 2008.

Radicalization: One of the most ineffable but also one of the most potent manifestations of spillover is the tendency for a civil war in one country to galvanize and radicalize neighboring populations. They regularly radicalize neighboring populations when a group in a neighboring state identifies with a related group caught up in the civil war across the border. These tribal, ethnic, and sectarian feelings always predate the conflict, but the outbreak of war among the same groups just across the border makes them tangible and immediate — giving them a reason to hate neighbors and resent their own government.

They may demand that their government or community leaders act to support one side or another. Alternatively, they may agitate for harsh actions in their own countries against groups they see as sympathizing with the enemy side over the border. Thus, the Iraqi civil war of 2005-2007 galvanized Sunnis in Egypt, Jordan, the Maghreb, and the Persian Gulf states both to demand that their own governments do more to support the Iraqi Sunni groups and (at least in the Gulf) to demand harsher treatment of their own Shiite populations.

At its most dangerous, this aspect of spillover can contribute to civil wars next door. The Lebanese civil war that began in 1975 prompted the Syrian Sunnis to launch their own civil war against Bashar al-Assad’s father in 1976, a conflict that only ended with the horrific massacre of 20,000-40,000 people at Hama in 1982.

Intervention: But perhaps the most dangerous form of spillover is when neighboring states intervene in a civil war, transforming a local conflict into a regional one. Perversely, the goal is often to diminish the risks of spillover such as terrorism and radicalization. But it can take many forms: intervening in a limited fashion either to shut down the civil war, to help one side win, or just to eliminate the source of the spillover. Occasionally, a neighboring state will see a civil war as an opportunity to grab some long coveted resource or territory.

Typically, even limited intervention by a regional power only makes the problem worse. Countries get tied to "clients" within the civil war and end up doubling down on their support for them. They assume that "just a little more" will turn the tide in their favor. Worse still, they can see neighborhood rivals intervening in the civil war and feel compelled to do the same to prevent their enemy from making gains. So when Rwanda and Uganda intervened in Congo in the mid-1990s to drive the genocidaires out of the refugee camps and topple the hostile regime in Kinshasa that supported them, so too did Angola, which sought to block them. As the conflict wore on, several powers tried to carve out buffer zones where their preferred proxies would rule — and where they could grab some of Congo’s abundant natural resources. Seven of Congo’s neighbors ended up intervening, turning the Congolese civil war into what became known as "Africa’s World War."

At its worst, this pattern can produce direct conflict between the intervening states over the carcass of the country in civil war. Syria first intervened in Lebanon in 1975 to end the radicalization of its own Sunni population. But the Syrians soon found that diplomacy, covert action, and support to various proxy groups were inadequate and reluctantly launched a full-scale invasion the following year. For its part, Israel suffered from terrorism emanating from the Lebanese civil war and covertly supported its own proxies, launched targeted counterterrorism operations, and even limited military incursions, before deciding in 1982 to invade to try to impose a single (friendly) government in Beirut. The result was a conventional war between Israel and Syria fought in Lebanon. But even winning did little for Israel. Thirty years later — 18 in painful occupation of southern Lebanon — Israel still faces a terrorism problem from Lebanon, and the Jewish state’s nemesis, Hezbollah, born of the Israeli invasion, dominates Lebanese politics.

Bad Signs in Syria

Our 2006 study also examined the factors that lead to the worst forms of spillover. They include ethnic, religious, and other "identity" groups that are in both the country caught in civil war and its neighbors; neighboring states that share the same ethno-religious divides being fought over by the country in civil war; fragile regimes in the neighboring states; porous borders; and a history of violence between the neighbors.

Unfortunately, Syria and its neighbors exhibit precisely these traits, explaining why we are already seeing the typical patterns of spillover from the Syrian civil war, and why spillover from the conflict could get much worse.

The Syrian conflict has produced more than 120,000 officially registered refugees, but the real figure is closer to 300,000. Turkey has 43,000 registered refugees from Syria and probably more than 25,000 that have not registered. The Turks believe that the Kurdistan Worker’s Party (PKK), a separatist Kurdish terrorist group, is using this population to infiltrate Turkey to launch a new violent bid for independence. Ankara is convinced that PKK fighters allied with the Alawite regime have taken control of parts of Syria, particularly in ethnically Kurdish areas of the country. In response, Turkey is aggressively enforcing the sanctity of its border even as it assists Syrian refugees who are taking the fight back home. Public opinion in Turkey is strongly anti-Assad, and popular frustration grows as Ankara seems unable to stem the violence.

Iraq is already struggling to avoid sliding back into its own civil war. It doesn’t need any pushing from Syria, but that is just what it is getting. Iraqi Sunnis identify wholeheartedly with their Syrian brethren whom they see as fighting against a Shiite-dominated government backed by Iran — which they see as an exact parallel with their own circumstances. External support to the Syrian opposition from Saudi Arabia, Qatar, and other Sunni Arab governments is reportedly flowing through the Sunni tribes of Western Iraq, many of which span the Syrian border. This support appears to be an important cause of the resurgence of al Qaeda in Iraq and the worsening sectarian violence there. The Iraqi regime (rightly) claims that it is fighting the same terrorists that the Alawite Syrian regime is struggling with on the other side of the border. As the Alawites are a splinter of Shiism, the growing cooperation between Damascus and Shiite-dominated Baghdad is feeding Sunni fears of a grand Shiite alliance led by Iran. All of this conjures a self-fulfilling prophecy about sectarian war.

Meanwhile, Iraqi Kurds are now contemplating a bid for independence in a way that they haven’t for many years. Key Kurdish leaders, including Kurdistan Regional Government President Massoud Barzani, have concluded that they cannot work with Prime Minister Nouri al-Maliki — whom they routinely brand as a "Shiite Saddam." And they increasingly believe that Turkey might eventually be persuaded to support such a bid. This makes whatever happens with Syria’s Kurds of particular importance. Indeed, Barzani and the Turks are wrestling against the PKK and the Syrian regime for the loyalty of Syria’s Kurds, who might well attempt to declare independence, putting pressure on Iraq’s Kurds to do the same.

Lebanon may be suffering the worst so far. It is inundated with Syrian refugees — 30,000 have registered with the United Nations High Commissioner for Refugees, but the latest spike in violence probably added at least another 10,000 — a number the tiny country simply cannot handle. The Syrian conflict is tearing at the seams of Lebanon’s already fragmented politics. Its Sunnis champion the Syrian opposition while Shiite Hezbollah backs the Syrian regime, provoking gunfights in the streets of Beirut and Tripoli. Meanwhile, Saudi Arabia is reportedly funneling arms to the Syrian opposition through Sunni groups in Lebanon and opposition groups are building bases in Lebanon, triggering reprisal attacks by Syrian regime forces and their Hezbollah allies.

So far, Jordan has escaped relatively unscathed, but that may not last. Amman already faces huge challenges from its Palestinian and Iraqi refugee populations, and now refugees from Syria have begun to flow in (almost 40,000 officially at last count, but other sources put the number closer to 140,000). Syrian army and Jordanian border patrol forces have clashed as the Jordanians have tried to help Syrian refugees. Moreover, many Jordanians, including not only those of Palestinian descent but also the monarchy’s more traditional supporters, have lost patience with King Abdullah II’s endless unfulfilled promises of reform triggering rioting and terrorism there unrelated to Syria’s troubles. More refugees, terrorism, and a further radicalized population could be more than the Hashemite Kingdom can take.

Remarkably, Israel has gotten off scot-free, so far. While we can all hope that will last, it would be foolish to insist blindly that it will.

The longer the civil war in Syria lasts, the more likely it is that the spillover will get worse. And it’s possible this war could drag on for months, even years. The United States and other powerful countries have shown no inclination to intervene to snuff out the conflict. Within Syria, both the regime and the opposition have shown themselves too powerful to be defeated but too weak to triumph. The war has also left the country awash in arms, so any new government will face a daunting task unifying and rebuilding the country. Most ominously, the opposition is badly divided, so victory against Assad might simply mean a shift to new rounds of combat among the various opposition groups, just as Afghanistan’s mujahideen fell to slaughtering one another even before they finished off the Soviet-backed regime there in 1992.

In the best case, the current problems will deepen but not explode. Refugee flows will increase and impose an ever greater burden on their host countries, but the stress won’t cause any to collapse. Terrorism will continue and more innocent people will die, but it won’t tear apart any of the neighboring states. And, from the narrow perspective of U.S. interests, the violence would remain focused within Syria rather than becoming regional, let alone global. Various groups — starting with the Iraqi Kurds — will continue to flirt with secession and other tensions will simmer, but none of these factors will boil over. The neighbors will provide some forms of support to various groups within Syria without crossing any Rubicons. Overall, the Middle East will get worse but won’t immolate.

This best case is not very good, and unfortunately it’s also not the most likely. Worse scenarios seem more plausible. The fragility of Lebanon and Iraq in particular leaves them vulnerable to new civil wars of their own. It might be hard, but it is not impossible to envision a regional war growing from the Syrian morass. Turkey seems like the primary candidate to up its involvement in Syria. Fears that Kurdish secessionism may spread, mounting criticism that the regime is ignoring atrocities next door, or a risky belief that Ankara could tip the balance in favor of one faction over another might eventually lead the Turks to intervene militarily — grudgingly and in a limited fashion at first, of course. If the plight of the Assad regime worsens, and if the Turks are heavily engaged, Iran might press Baghdad to increase its direct support of the Alawites and step up its own aid. Baghdad will be reluctant, but it might feel more inclined to do so if the Turks continue to support the Iraqi Kurds in their fight with the central government and if worsening internal divisions in Iraq — doubtless exacerbated by spillover from Syria — leave the Maliki government even more dependent on Iranian support.

An embattled Alawite regime — especially one facing ever greater Turkish intervention — might opt to employ its chemical warfare arsenal or, alternatively, amp up terrorist attacks on Israel to try to turn its civil war into an Arab-Israeli conflict, a development that could turn public and regional opinion in favor of the regime and discredit Assad’s opponents. Under those circumstances, Israel might mount limited military operations into Syria to take out its chemical weapons caches or terrorist bases, which no doubt would have repercussions among Syria’s neighbors and Arab states in general.

So far, the humanitarian nightmares of Syria have evinced little more than pity from the American people and only modest aid from their government. After a decade-plus of war in Afghanistan and Iraq, there is justifiably deep ambivalence about new military commitments in the Middle East. Stories of the humanitarian nightmares of Syria have evinced little more than pity from the American people. This creates a dilemma for the Obama administration and concerned Americans as they watch Syria burn: They have no interest in getting involved, but standing idly by is risky. If spillover from Syria worsens, squaring this circle could prove a major challenge.

At the very least, Washington should place a premium on keeping the Syrian civil war from dragging on indefinitely. Stepping up our efforts to arm, train, and unify the Syrian opposition factions that matter most — those fighting the regime within Syria rather than those squabbling outside it — would be a good place to start. Progress is likely to be limited, but Washington carries a bigger stick than the regional allies already backing Assad’s opponents and U.S. leadership can help prevent them from working at cross purposes. Supporting the efforts of our regional allies to feed, shelter, and police their refugee communities would be another option. Some neighbors could also use help dealing with their own political and economic problems, which could help them better weather the spillover from Syria. And some medicine might be needed along with the sugar: Pressing our regional friends to begin overdue reforms will help mitigate the discrimination and misery among their own populations that can act as kindling when sparks from Syria come flying their way.

The Syrian civil war is undoubtedly a tragedy for the people of that country. The longer it burns, though, the more likely it will ignite something much worse. However difficult it is to end the fighting today, it will be even harder as the violence snowballs and spillover grows. Less can be more when it is soon.

Kenneth M. Pollack is a senior fellow at the American Enterprise Institute.

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