President Obamaannounced on Friday that he had ordered several dozen Special Operations troops intoSyria for the first open-ended mission by United States ground forces in that country, deepening American involvement in a war he has tried to avoid for more than four years.
While the deployment was small in scale, it was large in importance for a president who had refused to commit American ground forces inside Syria beyond quick raids. White House officials said the troops would advise local forces fighting the Islamic State and not play a direct combat role, but they left open the possibility of sending more in the future.
The escalation came just weeks after Russia inserted itself into the multisided civil war to support President Bashar al-Assad, bombing opposition forces, including some supported by the United States. Although not characterized as a response, the dispatch of American troops further complicates a kaleidoscopic battlefield with varied forces and sometimes murky allegiances.
The move was meant to bolster diplomatic efforts by Secretary of State John Kerry, who on Friday reached an agreement in Vienna with countries with opposing stakes to explore “a nationwide cease-fire” and ask the United Nations to oversee the revision of the Syrian Constitution and then new elections. The accord represented the first time all the major outside participants had agreed on the start of a political process to bring the war to an end.
But a truce remained elusive and the president’s military move was the latest incremental step into the expanding conflict in Syria and next-door Iraq. Once intent on just using American airpower to help local forces on the ground, Mr. Obama has now sent 3,500 American troops to Iraq. AnAmerican soldier was killed in a commando raid last week, the first such casualty since the fight against the Islamic State began last year.
The troops heading to Syria will number “fewer than 50,” the White House said, but Pentagon officials said even those numbers would be useful in coordinating efforts with Kurdish forces. Republicans argued it was too little and too late to make a meaningful difference, while some Democrats said it pushed the United States further down a slippery slope into a hopeless war.
The White House insisted this was not a case of mission creep. “The mission has not changed,” said Josh Earnest, the White House press secretary. “These forces,” he added, “do not have a combat mission.”
“The responsibility that they have is not to lead the charge to take a hill, but rather to offer advice and assistance to those local forces about the best way they can organize their efforts to take the fight to ISIL or to take the hill inside of Syria,” he said.
But the definition of combat has shifted since the United States last year began taking on the Islamic State, also called ISIS or ISIL. In May, Delta Force commandos entered Syria aboard Black Hawk helicopters and V-22 Ospreys and killed an Islamic State leader and about a dozen militant fighters. The soldier killed last week was part of a force accompanying Kurdish commandos on a raid to free prisoners held by the Islamic State.
In addition to the Special Operations deployment, Mr. Obama authorized deploying A-10 and F-15 warplanes to Incirlik Air Base in Turkey. The A-10s are capable of providing close in-air support to fighters on the ground. The F-15s can carry out a range of air-to-ground combat missions.
Mr. Obama, who spoke with Prime Minister Haider al-Abadi of Iraq on Friday, instructed advisers to consult the Baghdad government about establishing a Special Operations task force to further efforts to target Islamic State leaders there. He also ordered more military assistance to Jordan and Lebanon.
The Pentagon wants to build a firewall behind forces allied with the United States — both the Kurds and the Syrian-Arab coalition backed by Mr. Obama — to allow these fighters to hold territory they have captured. Part of the way to do that, one Defense Department official said, is to ensure that equipment is delivered and that subsequent supplies will reach these forces quickly.
The shift represents “a kind of Goldilocks policy — not too hot and not too cold,” said Aaron David Miller, a vice president with the Woodrow Wilson International Center for Scholars. “Keep your eye on ISIS, keep your forces out of Russia’s way and yet enhance your profile after Moscow has raised theirs.”
At the moment, officials said there was no plan to send the American troops beyond a makeshift opposition group headquarters in northern Syria. They will not patrol or travel with opposition groups. Officials, though, also said that could change as the situation warrants. And they said no decision has been made on sending additional Apache helicopters to Iraq.
The move could potentially put the American troops in the cross hairs of Russia, which last month began airstrikes on antigovernment forces in Syria. A senior Pentagon official said the United States had not informed Moscow about where the American forces will be. “The area where we are planning to place these special operators is not an area where they have struck or where they would need to strike,” the official said. “It’s not ISIL or regime-controlled.”
But given that most Russian airstrikes have been against opposition groups that are not part of the Islamic State, there is no guarantee that Moscow may not hit groups in which the American forces are embedded. That said, Russia has “significant visibility” over what happens in Syria, the official said, adding that if it becomes necessary to keep its troops safe the United States will communicate with Moscow.
But Mr. Miller and other foreign policy specialists warned that the move risked alienating Turkey since it will bring American forces into an even closer alliance with northern Syria’s Kurdish fighters, including Kurdish People’s Protection Units, which have come under attack from Turkey in recent days.
Derek Chollet, a former assistant defense secretary under Mr. Obama, said the administration would seek to calm Turkish concern by saying the move would help protect its interests. “After all, the Turks have wanted U.S. Special Forces on the ground in Syria for years,” he said.
The diplomatic progress reported in Vienna came after seven hours of heated negotiations, punctuated by sharp exchanges between the foreign ministers of Iran and Saudi Arabia. But it amounted to more of an aspiration than a settlement.
Mr. Kerry and the other diplomats set no deadline for either the cease-fire or a new constitution and election that would follow, and it remained unclear whether Mr. Assad, who was not invited, or the rebels seeking to overthrow him will agree. But the diplomats will meet again in two weeks to expand on the basic principles issued on Friday night, including a commitment to keep Syria together as a single nation.
Mr. Kerry and his Russian counterpart, Sergey V. Lavrov, the foreign minister, announced the results together, but they remained deeply divided on whether Mr. Assad must step down as part of any final resolution, as the United States and its European and Persian Gulf allies have demanded and Russia and Iran have resisted.
“We have no agreement on the destiny of Assad,” Mr. Lavrov told reporters as he sat next to Mr. Kerry. “Russia believes that it is up to Syrian people to decide within the framework of the political process.”
Laurent Fabius, the French foreign minister, said Mr. Assad’s eventual departure remained a necessity. “As far as we are concerned, we think that Bashar al-Assad has no place in the future of Syria,” he said.
Both Mr. Kerry and Mr. Lavrov said the cease-fire would not apply to the conflict with Islamic State forces. Mr. Lavrov declined to criticize, at least publicly, the American decision to send Special Operations forces to northern Syria. Mr. Kerry told reporters the timing of the announcement was “a coincidence” and that he was not aware a decision had been made until earlier Friday.
The two men said they discussed coordination of their attacks beyond the narrow conversations about avoiding an accidental conflict. “We have some ideas which we discussed today that I am taking back to Washington,” Mr. Kerry said.
Still, the tensions in Vienna emphasized how difficult it could be to reach a common understanding. The most heated conversations took place between Iran’s foreign minister, Mohammad Javad Zarif, and his Saudi counterpart, Adel al-Jubeir. Until a few days ago, the Saudis refused to sit in the same room with the Iranians and they spent much of the meeting “voicing grievances and accusations,” said one official.