Putin's statement that he will continue to sell weapons to Syria isn't going to be enough. To have any chance to deter the madman in the White House, Putin has to say and mean that he will defend Syria, and communicate that view widely to Congress and the American people. Maybe even that wouldn't work, but it is the last chance at deterrence before war.
I am sure Putin explained “the facts of life” to Obama privately — but he may not have been listening, was probably too busy getting prepped to meet with the Russian GLBT group. (He talked with Putin for 20 min, but met with the LGBT group for an hour — shows where his priorities lie)