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REUTERS/Sergei Karpukhin
Putin is sending a message to the international leaders who want Assad's out.
Now a war that saw Western, Turkish, and Gulf proxies in addition to Syrian army defectors on one side fighting Iranian proxies and Russian hardware backing the regime of Bashar al-Assad on the other has reached a new level.
"We've already moved one step beyond a proxy war, where the Americans/Europeans and Russians are arming two opposing sides in a war ... to where the Russians are now directly fighting Western proxies," Ian Bremmer, president of Eurasia Group, told Business Insider via email.
"The danger is that we move one step further still."
Putin and Obama had reportedly agreed about fighting ISIS and opening lines of communication between their militaries to prevent an accidental conflict that could lead to all-out war.
Nevertheless, Syrian skies are quite crowded as Russia targets CIA-backed rebels in coordination with Iran and the Syrian regime.
"US officials say they now believe the Russians have been directly targeting CIA-backed rebel groups that pose the most direct threat to Mr. Assad since the campaign began on Wednesday, both to firm up regime positions and to send a message to Mr. Obama's administration,"Adam Entous of The Wall Street Journal reports.
In 2013, President Obama authorized the CIA to begin training and arming a group of moderate Syrian rebels to put pressure on the Assad regime. By attacking these CIA-backed rebels directly, Russia is now challenging the Obama administration to either intervene or look away
"Russian president Vladimir Putin's was the most significant geopolitical victory scored against the United States since the end of the cold war," Bremmer said.
"Putin has embarrassed President Obama by pointing out the credibility gap between stated policy ('Assad must go, ISIS must be destroyed') and American willingness to actually bring about the removal and destruction," Bremmer said.
"So there's a geopolitical vacuum which the Russians have now, partially (and only very partially) filled."
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REUTERS//Pablo Martinez Monsivais
Obama talks with Putin during arrivals for the G20 summit at the Konstantin Palace in St. Petersburg, September 5, 2013.
Yesterday, two US
A senior Russian lawmaker also told the Interfax-AVN news agency that Russian "volunteers" who have honed their combat skills in Ukraine will likely travel to Syria to fight alongside pro-regime forces.
'And then there's a wildcard'
The US is not the only power the Russians are challenging in Syria.
"And then there's a wildcard: Turkey," Bremmer noted. "The NATO ally most deeply destabilized by Assad's civil war, with a lengthy and porous border with Syria, Kurds pouring into Syria to fight Assad, while some 2,000,000-plus refugees have come into Turkey in the other direction."
Ankara has long sought Syrian President Bashar Assad's transition out of power. To this end, Ankara been supporting some of the most powerful rebel groups in northern Syria since the civil war began in 2011- groups that Russia has also been bombing.
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REUTERS/Ivan Sekretarev/Pool
Russian President Vladimir Putin (R) meets with Turkish President Tayyip Erdogan at the Kremlin in Moscow, Russia, September 23, 2015.
And Moscow's intervention has increased the possibility that Russia will end up in a direct military confrontation with Turkey. Turkish officials were quick to express "serious concern" over the airstrikes but tensions rose over the weekend when a Russian war plane violated Turkish air space south of the Hatay region.
"We are greatly concerned about it because it is precisely the kind of thing that, had Turkey responded ... it could have resulted in a shoot down, and it is precisely the kind of thing we warned against," US Secretary of State John Kerry said during a visit to Chile.
On its first day of airstrikes, Russia demanded that the US exit Syrian airspace to avoid any unintentional accidents. The US refused to end its own air campaign, but has been working with Russia to try and "deconflict" certain areas where American and Russian planes risk coming into contact.
There is no comparable "deconflicting" going on between the Turkish and Russian militaries at this point, and if Turkey moves to establish a buffer zone in northern Syria, the Russians will inevitably oppose it.
REUTERS/Denis Sinyakov A Russian SU-30 fighter jet.
"The Russians will not meddle in the north," Salih Muslim, cochair of the Kurdish Democratic Union Party, said in an interview with al-Monitor last week. "But should Turkey attempt to intervene, then they will."
"Russia has a joint defense agreement with Syria," Muslim added. "They will prevent Turkish intervention not to defend us [Kurds] but to defend Syria's border."
The possibility that Russia and Turkey end up in direct military conflict is "the biggest danger that comes from the Russian intervention," Bremmer said, because it would force NATO to come to Turkey's defense and escalate the conflict to a whole new level.
"There's plenty of reason to believe calmer heads would prevail and deterrence would hold in such a scenario," Bremmer said "But we'd really rather not test that."