Whatever his other failings at the G-20 summit on Thursday, U.S. President Barack Obama still made the grandest entrance. Driving up to the venue — an imperial palace in the Russian city of St. Petersburg — the other world leaders looked almost dowdy in their Mercedes and BMW sedans, at least when compared with Obama in his stretched Cadillac Escalade, which his press pool dubbed the Beast. In an apparent gesture of goodwill toward the host country, Obama’s ride even strayed from the usual protocol by flying the Russian tricolor, complete with little golden tassels. But Russian President Vladimir Putin, standing at the palace door, looked unimpressed. He was not there to make friends with Obama.

On the most pressing issue of the summit — how to deal with the civil war in Syria — Putin and Obama have taken opposing positions in the past few days. Obama has called for a military strike to punish the Syrian government for its alleged use of chemical weapons against its own people. Putin, who has accused the Obama Administration of lying to justify another war in the Middle East, has countered that any attack against Syria would be an illegal act of aggression unless it got approval from the U.N. By the time the world leaders gathered for the G-20 on Thursday afternoon, it was clear that most of them were much closer to Putin’s position. Apart from France, no one was ready to take up arms with the U.S. in Syria.

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The clearest blow to U.S. coalition-building at the summit came from the leaders of the E.U. In a briefing on Thursday afternoon, European Commission President José Manuel Barroso said the Syrian conflict was a “stain on the world’s conscience,” but stressed that the E.U. believes in a “political solution” to the crisis. Standing beside him, E.U. President Herman van Rompuy drove this point home. “There is no military solution to the Syrian conflict. Only a political solution can end the terrible bloodshed,” he said. Of all E.U. members, he added, “only France is ready to cooperate” with the U.S. on a military strike. So Europe’s joint statement at the G-20 would urge the U.N. Security Council to deal with the crisis politically, he said, echoing a point that Putin has long been making. (The U.S. insists that its proposed military action is not aimed at ending the war, but, rather, aimed at undermining Assad’s ability to deploy chemical weapons.)

But since the Syrian war began more than two years ago, all U.N. initiatives have been shot down by Russia and China, who have both vetoed the last three resolutions on Syria in the U.N. Security Council. China, predictably, signaled its opposition on Thursday to any military strike against Syria, with Chinese Vice Finance Minister Zhu Guangyao saying it would have a “negative impact on the global economy, especially on the oil price.” A few days before the summit, Putin said it is “utter nonsense” to suggest that the Syrian regime could have used chemical weapons against its own people, leaving little room to hope that Russia would accept any proof to the contrary. As for the proof that the U.S. has already presented, Putin’s spokesman Dmitri Peskov said on Thursday that it was “very far from convincing.” The Obama Administration, Peskov suggested, has been “shaping the facts to justify its need to strike.”

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The heads of the world’s biggest developing nations, who formed a major bloc within the G-20, seemed to agree, Peskov said. Collectively known as the BRICS, the group comprising Brazil, Russia, India, China and South Africa met apart from the Western delegates at the summit, in part to coordinate their positions early in the day. According to Peskov, feelings against the U.S. ran high at that meeting. In particular, the five leaders expressed “harshly negative” reactions to last month’s news that the U.S. had systematically spied on them. Those revelations were based on leaks from the former U.S. intelligence contractor Edward Snowden, who was granted asylum in Russia last month. At their meeting on Thursday, the BRICS leaders said that these electronic spying operations were “comparable to terrorism,” Peskov said at a press conference during the summit.

So by the time all the G-20 delegates pulled up to the Konstantin Palace, Obama was not the most popular man around, while Putin’s positions were clearly gaining support. That afternoon, the main G-20 roundtable was held in the palace’s Marble Hall, whose ceiling is decorated with an image of Mars, the Roman god of war, raising a sword over his head. It seemed a fitting symbol of the choice that hung over the summit — the choice of another American intervention in the Middle East — and not too many of the delegates seemed to like the look of that sword.