Russia has expanded its military operations in Syria to include a second airbase as well as other posts, according to a U.S. official briefed on the latest intelligence from the region – even as President Obama expresses muted optimism that Russian President Vladimir Putin eventually will “shift” his strategy and work with the West.

Moscow’s presence has grown to a total of four forward operating bases, including recently added bases in Hama and Tiyas. But the most concerning to the Pentagon is the second airbase in Shayrat which can support fixed-wing aircraft, greatly expanding Russia’s capability for airstrikes, which began on Sept. 30.

“The Russians are operating helicopters out of Shayrat airport, but they are making [preparations] to land fixed-wing aircraft,” another U.S. official confirmed to Fox News. […]