WASHINGTON – Five years since guns first silenced protesters in Damascus, the chief benefactor of Syria’s embattled government, Russian President Vladimir Putin, announced Monday he would withdraw the bulk of his troops from the country, declaring his military objectives there complete.The announcement marked a critical moment in the arc of a long war in which Syrian President Bashar Assad has viciously battled for survival.“'I will not run.'”The White House said it was monitoring the news.“We have seen reports that President Putin has announced a planned withdrawal of Russian forces from Syria,” a senior administration official told The Jerusalem Post shortly after the announcement. “We expect to learn more about this in the coming hours.”When Assad was running short on troops last September, Moscow dramatically increased its military support for his government, directly intervening on the ground and by air with an effective campaign against rebels fighting for his overthrow. The result was a complete battlefield shift in Assad’s favor, and Russia’s effort to change facts on the ground boosted his chances of remaining president as talks in Geneva begin this week toward a political transition and nationwide elections.Entering those talks, Assad’s foreign minister said discussions over the presidency were off the table. The rebels’ High Negotiations Committee – backed by the US, Turkey and the Gulf states – accused Damascus of attempting to scuttle the talks before they began.In addition, Putin has ordered his Foreign Ministry to “intensify” Russia’s role in the UN-brokered political process, he said in a televised speech.“The effective work of our military created the conditions for the start of the peace process,” Putin said. “I believe that the task put before the Defense Ministry and Russian armed forces has on the whole been fulfilled.”When the intervention first began last year, Moscow’s stated goal was the eradication of “terrorist” groups from Syria, ranging from those classified as terrorist organizations by the United Nations, such as the Nusra Front and Islamic State, to those simply opposed to Assad, such as the Free Syrian Army.Syria’s rebels have lost ground but they are hardly defeated, and Islamic State has remained virtually untouched by Russia’s air campaign, leaving unanswered questions behind Moscow’s sudden change of heart.In a call on Monday, Putin and Assad agreed Russia would continue helping Damascus in “confronting terrorism.”Assad, meanwhile, said he hoped for “concrete results” from the Geneva negotiations, according to Russian media reports.Talks began in Geneva on Monday after fits and starts throughout the month of February. The “proximity” talks – in which UN personnel shuttle between Assad and rebel delegates, camped in different rooms – are scheduled to spread over three two-week rounds, with short breaks.By the end of April, the world will know whether a political solution is viable for Syria, said the UN’s special envoy for the crisis, Staffan de Mistura.“As far as I know, the only Plan B available is return to war, and to even worse war than we had so far,” Mistura said.The spiraling conflict in Syria has presented US President Barack Obama with the greatest challenge of his presidency.For Europe it has meant a test of the EU under the pressure of migrant flows, for Russia it has posed an identity crisis over its role in the world, and for the Middle East it has opened fundamental questions over its century-old state structures.But for the Syrian people themselves, five years of civil war have robbed a third of its children of a world without ceaseless violence, creating 2.4 million child refugees and killing thousands more, according to the United Nations Children’s Fund. They are only a fraction of the 13.5 million people – over half of the country’s population – displaced by the fighting, including six million who are internal refugees, and more than million who have fled the country.On Tuesday, Syrians could mark the grim anniversary with something to celebrate: a pause in fighting, if only temporary, brokered by Washington and Moscow.An open-ended “cessation of hostilities” has held for two weeks now, intended to lay the groundwork for diplomacy in Geneva considered to be Syria’s last, best hope of reaching a political solution to the crisis.But the direct involvement of so many foreign powers – over 20 in all, each with special interests in the outcome of the war – speaks to how far the conflict has evolved from its origins, in March of 2011, when 15 children disappeared in the southwestern city of Daraa, near Jordan, after drawing anti-government graffiti, something that prompted protests.On March 15 of that year, rallies swept Damascus and Aleppo, where protesters chanted for democratic reforms. They appeared in sync with a larger movement sweeping the Middle East – the so-called Arab Spring that inspired hope in Western capitals that the region might mature from within at last. But on that day, protesters were met with government force. Syria’s civil war began as a revolution.Every diplomatic effort to end the fighting in Syria has been stifled by differing interpretations over what happened during that critical moment and whether the government’s crackdown on protesters was justified. The Free Syria movement says it will never stop fighting until Assad departs, yet the powers supporting him – Russia and Iran – have made the same arguments in his defense to this day, five years to the date, as negotiations in Switzerland focus squarely on Assad’s fate and his legitimacy as president.Russian officials say they are no longer wedded to maintaining Assad in a future Syria.Their announcement of a troop pullout could signal one of two strategies: the belief that Assad has permanently solidified his gains or that he should feel exposed as he enters a critical round of negotiations.The talks in Geneva are scheduled to run through March 24 before recessing for a week, according to UN officials.“Four words can end this war,” Kerry said in February, referring to Assad at a committee hearing on Capitol Hill.