WASHINGTON - After 2 1/2 years of civil war in Syria, President Barack Obama's larger policy is in disarray even as his administration, with help from Russia, averted a military showdown for the time being.
In an address to the American people, Obama said he was working with U.S. allies to "provide humanitarian support, to help the moderate opposition and to shape a political settlement" for ending a conflict that has killed more than 100,000 people and made refugees of millions more.
That simple message belies a hodgepodge of often contradicting goals and strategies unlikely to be resolved by the new international effort to get Bashar Assad's government to relinquish its chemical weapons or by any U.S. military action if diplomacy fails.
These include Obama's vacillations on providing military assistance to rebels as part of a peace strategy and his repeated demand that Assad relinquish power but still retain a veto over any replacement government.
The difficulty in understanding what America is trying to do in Syria has persisted in the current debate over how to respond to the Assad government's alleged use of chemical weapons.
Threatening military reprisals, Obama said that the "United States military doesn't do pinpricks" only a day after his top diplomat, Secretary of State John Kerry, promised an "unbelievably small" operation.
The administration's top national security officials have spoken ambiguously about doing anything militarily to shift the battlefield momentum toward rebels trying to overthrow the Syrian leader - a stated U.S. policy objective.
In the last few days Obama has turned again to help from Russia, a Syrian ally the U.S. repeatedly has accused of being complicit in the Assad government's wartime atrocities.
A look at how U.S. policy in Syria has evolved:
THE END OF ENGAGEMENT
Arab Spring-inspired demonstrations erupt across Syria in March 2011. The unrest comes as the Obama administration is hoping to coax Assad into ending Syria's alliance with Iran and support for militant groups Hamas and Hezbollah. As the protests spread and reprisals worsen, U.S. engagement narrows to trying to get the Syrian government to respect political opponents and move toward democracy.
Amid calls for a tougher U.S. response, then-Secretary of State Hillary Rodham Clinton says Assad is seen by some U.S. lawmakers as a "reformer." Days earlier, Kerry, then a U.S. senator, argues that Syria is poised for change "as it embraces a legitimate relationship with the United States and the West." The administration resists calls over the next months to recall the U.S. ambassador, the first senior American posted to Damascus in five years. Obama reacts to increased brutality by Assad's forces in April by ordering the first of several new sets of sanctions against Syria. Violence escalates, with Assad sending tanks into cities throughout the summer. Citizens and defecting soldiers take up arms against government. By August, Obama has seen enough. He publicly calls on Assad to resign.
REBUFFED AT THE U.N.
The U.S. and allies take their case to the United Nations in October 2011, asking the Security Council to condemn human rights violations in Syria and demand an end to violence. Russia and China veto the resolution. That month, the U.S. pulls Ambassador Robert Ford out of Damascus because of security concerns as Washington's relationship with Assad's government worsens. Ford returns in December, then leaves for good two months later. The U.S. tries anew at the U.N. in February 2012, backing an Arab-proposed plan to hold Syrian human rights violators accountable. Russia and China again exercise their veto; Clinton calls their actions "despicable."
Stymied at the U.N., the U.S. turns to its Arab and European allies and convenes the first "Friends of Syria" conference in Tunisia to find ways to support Syria's opposition and weaken Assad's control. U.S. intelligence officials start warning for the first time about al-Qaida and other extremist militants joining the fray. Still hopeful of finding a peaceful resolution, the U.S. urges that no one send weapons to either the government or the rebels. The violence worsens. In March 2012, Obama pledges "nonlethal" aid to the rebels. The U.N. says about 8,000 are dead after a year of violence.
FALSE DIPLOMATIC HOPE
Secretary of State Clinton believes she secures Russia's commitment on a path forward in June 2012 with the "Geneva process." It calls for a Syrian transitional government through negotiation between Assad's government and the opposition. The diplomatic strategy is presented as a way out of the crisis because both Assad and the rebels would be able to veto any transition government candidates.
Within hours of signing on to the strategy, the U.S. and Russia bicker over whether the agreement includes Assad relinquishing power. Russia and China veto a third U.N. resolution in July after the U.S. and its allies try to make the agreement enforceable. The process fizzles out without delivering any peace talks or progress toward forming a new government. Arab governments disregard the U.S. call for a weapons embargo and supply the rebels with increasingly advanced weaponry. Obama rebuffs suggestions by Clinton, CIA Director David Petraeus and other senior U.S. officials to provide weapons to moderate opposition forces. By July, the U.N. says 5,000 Syrians are dying each month in the fighting.
Responding to worrying intelligence indications, Obama declares in August 2012 that the use or deployment of the Syrian government's chemical weapons stockpiles is a "red line," which if crossed would change America's calculus in the conflict. He says any such chemical weapons activity would entail "enormous consequences."
Rebel military advances stall. At the behest of Washington and others, the Islamist-dominated political opposition reforms itself in November 2012 to include more moderates and minorities. The U.N. puts the death toll since the beginning of the conflict at 60,000. In December, the U.S. recognizes the Syrian Opposition Coalition as the Syrian people's legitimate representative. U.S. humanitarian aid increases significantly. Washington also puts one rebel faction, the al-Qaida-linked Nusra Front, on the U.S. terrorism blacklist.
Obama starts his second term as president and Kerry replaces Clinton as secretary of state. The U.S. becomes more assertive in its rhetoric about shifting the Syrian civil war's momentum and trying to convince Assad that he cannot prevail militarily and should relinquish power.
In February 2013, the U.S. decides to send medical kits, ready-made meals and other forms of nonlethal aid directly to the rebels but refuses to join its Arab partners in providing weapons. In March, Syrian rebels and Assad's government accuse each other of using chemical weapons. The U.S. begins investigating. In May, Kerry travels to Moscow and revives the Geneva peace process. U.S. and Russian officials again differ on whether Assad must relinquish power. Like its predecessor, the "Geneva II" effort delivers no progress. Pressed by the U.S., the Syrian opposition rearranges itself again to include more women, minorities and moderate military representatives.
U.S. intelligence concludes in June that Assad's forces used small amounts of the nerve agent sarin in several attacks. Obama responds by authorizing the delivery of lethal aid to Syria's rebels for the first time. No weapons or ammunition are sent, however. The administration discusses but rejects trying to impose a no-fly zone over Syria.
Military officials express increasingly dire assessments of the role al-Qaida and other terrorist groups are playing in Syria and the options available for U.S. military intervention. By July, the U.N. secretary-general says more than 100,000 people have died. The war takes an even more ominous turn on Aug. 21 with a massive chemical weapons attack outside Damascus. Within days, the U.S. declares with "high confidence" that Assad's forces are responsible and says more than 1,400 people, including more than 400 children, were killed.
RED LINE CROSSED
Obama and top aides threaten limited military action. Four U.S. destroyers equipped with cruise missiles are put on standby in the eastern Mediterranean Sea. Kerry calls the attack a "moral obscenity" and lays out the early case for American intervention.
The Parliament in Britain, America's closest military partner, rejects using force in an Aug. 29 vote and U.S. officials raise the possibility of a unilateral American attack. Two days later, Obama surprisingly asks Congress for official authorization to strike. Kerry, Defense Secretary Chuck Hagel, Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, and other top national security officials hold a series of telephone calls, classified briefings and public hearings to present their argument for action. The president reaches out to lawmakers, hosting both skeptics of involvement and advocates of even stronger U.S. measures - such as Republican Sen. John McCain. He asks them and the public to unite behind his plan. Encountering resistance, the president and his advisers say he can act even if Congress rejects his request.
Democrats and Republicans in the House and Senate, many on summer break and hearing from citizens overwhelmingly against U.S. military action, increasingly voice opposition to Obama's strategy. Obama meets Russian President Vladimir Putin on the sidelines of a global economic summit on Sept. 6 and they discuss diplomatic alternatives to get Assad to surrender his chemical weapons stockpiles.
Obama asks Senate leaders on Sept. 9 to delay voting on authorizing military action. He addresses the nation on Sept. 10 and tries to persuade Americans to support military action in Syria if diplomacy fails. Assad's government announces its intention to sign the U.N. treaty banning chemical weapons and hand over its stockpiles. Diplomatic wrangling continues between the U.S. and Russia over how to verify that Syria lives up to the deal in a timely manner and what consequences it should face if it doesn't. U.S. officials say the Syrian rebels have received a first package of U.S. lethal aid.