Two deadly car bombings last weekend near Turkey’s border with Syria underscored what Turkish Prime Minister Recep Tayyip Erdogan will be looking for from President Barack Obama in Washington this week: stronger U.S. leadership on Syria’s civil war.

What Turkey wants specifically is U.S. support for arming rebel fighters in Syria and creating a no-fly zone to protect them. Obama should be open to these ideas, but he should also ask for actions by the Turks that would ease concerns over potential drawbacks of U.S. intervention.

The May 11 attacks, which killed about 50 people in an area that Syria has long claimed as its territory, demonstrated Turkey’s vulnerability to the bloodshed next door. Erdogan and his government quickly arrested nine people identified as members of a left-wing Turkish terrorist group with ties to Syria’s intelligence agency. The claims are unproven, but they show the Turkish government’s fear of contagion.

The Obama administration is, of course, equally concerned about Syria’s violence spreading. Yet the U.S. and Turkey have some very different views on the conflict that need to get resolved.

Radicals’ Threat

The first concerns extreme Islamist groups such as the al-Nusra Front, an al-Qaeda affiliate, that are fighting against President Bashar al-Assad’s forces. In Turkey’s view, U.S. worries over the growing role of these radicals are overblown and self-fulfilling. Turkey thinks that if mainstream rebel fighters were better armed and financed, then support for the militants would fall away.

Although there is truth to that view, the U.S. is rightly concerned that its weapons will end up in the hands of al-Qaeda. It also worries that a no-fly zone could help extremists to a victory that leaves them in charge of part or all of Syria, including its chemical weapons.

Obama should make it clear to Erdogan that the price of increased U.S. support would be for Turkey to lock down its territory as a transit point for foreign jihadis who are routinely seen arriving at Hatay Airport, headed for the war in Syria. It would also need to be more cooperative toward U.S. officials operating covertly in southern Turkey (Turkey has been less cooperative than Jordan in this regard). And it should speak out more clearly to condemn Islamist radicals, with the goal of marginalizing them, even if that hurts Turkey’s popularity with the rebels.

Second, Turkish policy assumes that with proper support, the more moderate Free Syrian Army can make a clean end to the fighting, after which the new regime would either drive Islamist radicals out of the country or eradicate them. The U.S. is less sanguine. It worries that victory will probably be messy and may result in a dismembered country, with rebel groups battling for wider control. Like the administration, we see the latest U.S.- Russian effort to broker peace talks as the ideal way to avoid such an outcome, though we hold out little hope.

Erdogan should understand that U.S. support on a scale needed to end the fighting quickly and cleanly isn’t possible -- ground troops are out of the question. As a recent International Crisis Group report notes, Turkey has become dangerously exposed by working so closely with the Syrian opposition, allowing rebel fighters to move freely and “blurring” the border with a former Ottoman province. Instead of assuming rapid regime change, the report rightly says Turkey should develop a more neutral policy toward Syria’s opposition factions, reaching out more to non-Sunnis and preparing for Turkey to work with whatever regime emerges from the war.

Religious Tensions

Third, the Syrian conflict and the sectarian fissures it has opened throughout the Middle East have pushed Turkey into the role of a Sunni power in the region. This isn’t a policy choice Erdogan made -- he reached out to Shiite Iran and to Assad, an Alawite, before the Arab Spring. He also deserves enormous credit for starting a peace process with the Kurdistan Workers’ Party, easing a severe source of tension in the region.

Still, Erdogan’s government needs to set out a more clearly nonsectarian agenda in Syria by reducing its commitment to the Sunni Muslim Brotherhood politicians and fighters it supports and publicly backing the formation of a transitional government based on the kind of secular constitution that would include Alawites, Christians and Druze minorities, as well as Sunnis.

Similarly, Turkey should look to repair damaged relations with the Shiite leadership in Iraq. Turkey angered the Iraqi government by supporting the Sunni opposition to Prime Minister Nouri al-Maliki in 2010 election, and last month agreed to a lucrative deal to ship oil out of Iraqi Kurdistan against fierce opposition from Baghdad, which says the deal is illegal.

Finally, Turkey’s leaders should recognize that they can’t advocate a regional, international intervention in Syria while grandstanding with Hamas in Gaza and criticizing Israel for its airstrikes on heavy-weapon convoys on their way from Syria to Hezbollah in Lebanon.

For Erdogan to get the U.S. military action he wants, he will need act more as a regional broker and less as the parochial leader of a Sunni state.

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