Really? I think it's a pretty clear message that Russia will not tolerate overt NATO involvement in Syria; a message that Obama will have to take very seriously while considering military options. You also have to consider the effects that this show will have on the morale of the rebels. Not only does it show that Russia is likely to prevent external military assistance, but it also demonstrates their willingness to intervene if Assad's rule is ever seriously threatened. Sometimes it doesn't take outright violence to defeat a rebellion. In 1989 the U.S. helped preserve Corazon Aquino's government in the Philippines simply by running combat patrols above Luzon. The show of force alone resulted in defections from the rebel ground forces and a slowing of their momentum. It may seem like a "meh" maneuver when Iran parks warships outside of New York, but it certainly isn't when the U.S. sends warships to the Strait of Hormuz, or the Russians send warships to the Levantine Sea.