Sen. Bob CorkerBob CorkerA guide to the committees: Senate Republicans play clean up on Trump's foreign policy GOP Congress unnerved by Trump bumps MORE (R-Tenn.) says Russian President Vladimir Putin is escalating his support for the Assad regime in Syria because he thinks the Obama administration won't stop him.
"He sees no pushback, no price to pay," said Corker, the chairman of the Senate Foreign Relations Committee, at the Washington Ideas Forum on Wednesday. "What he's doing is raising popularity in his country."
Russia says that it is only targeting the Islamic State in Iraq and Syria (ISIS), but administration officials are worried the military action is intended to shore up Syrian President Bashar al-Assad's regime.
Corker said he has seen reports that the Russian airstrikes are hitting targets other than ISIS, despite Russian assurances.
"They're even hitting rebels ... not people affiliated with ISIS," he said.
The Foreign Relations chairman also criticized the Obama administration for missing opportunities in Syria, citing the decision to pull back from its redline after the regime used chemical weapons.
"We have missed opportunities," he said, adding that there was a 10-hour operation planned. "No boots on the ground. ... That could have really changed the momentum at a time when we really did have a moderate opposition.
"By us not taking that action, it took the wind out of their sails," he said. "That was the biggest moment of opportunity ... and that was mishandled."
He said the Obama administration has considered "decision memo after decision memo" on establishing a no-fly zone, where humanitarian aid could be provided to civilians.
The Syrian civil war has led to a refugee crisis, with millions of people seeking to escape the violence.
Corker said Congress was likely to approve the administration's proposal to raise the number of admitted refugees from the current 70,000 a year to 100,000.
"My guess is ... it'll be supported," he said.
Corker said any U.S. strategy to end the four-year civil war in Syria that would go after ISIS but leave Syrian President Assad in place would be a "conflict of goals."
"Assad is the singular pull for ISIS in the region," he said.
Administration officials have said Assad must step down, but have recently softened their language on when that must happen.
Ben Rhodes, deputy national security adviser for strategic communications at the White House, who spoke after Corker at the forum, disputed the notion that Putin was operating from a point of strength. He suggested that Russia was trying to hold on to its waning sphere of influence in the Middle East and Ukraine.
Ultimately, he said, "there are no military solutions to these problems."