Russia’s Caspian Sea fleet fired 26 cruise missiles into Syria on Wednesday, escalating its weeklong incursion into the war-rattled country.

Allen Lynch, author of “Vladimir Putin and Russian Statecraft,” is a politics professor at the University of Virginia. He is available to comment on Moscow’s growing involvement and offers the following observations:

• The Russia intervention in Syria is part of Russia's internal security strategy. A collapse of the Syrian government would make Russia's southern borderlands much more vulnerable to radical Islamist penetration. It’s less than 500 miles from the northeast Syrian border to post-Soviet borderlands in the Caucasus, where Russia maintains a significant security presence (Armenia is a client state)– about the distance between Washington, D.C., and New Hampshire.
• Russian President Vladimir Putin has concluded from the U.S. interventions in Iraq (2003) and Libya (2011), as well as the obviously poor planning for possible intervention in Syria (2013), that U.S.-backed regime change will bring more instability than maintenance of existing authoritarian regimes. Backing Syrian President Bashar al-Assad is the least bad of not-good choices.
• Note the care with which the Russians have executed their intervention: they are based on the coast, which means that their forces cannot be surrounded and can be withdrawn quickly should circumstances warrant.
• Putin does not need this intervention to boost his domestic political support, which is still in the 80-percent range. In fact, a large majority of the Russian public was opposed to such an intervention, as previous Russian polls made clear and which Putin was certainly aware of. 
• Backing the only visible source of state authority, even within a limited area, is not on the face of it unreasonable. Russia is not trying to help Assad retake all of Syria, but to see if it can bolster Assad’s regime within an area near the coast containing the majority of Syria's population. If it works, all the better and Russia also develops a working alliance with Iran and ex-U.S. client state Iraq. If it fails, he can get out on the cheap having made a strong but limited commitment.
• Putin's prime motive is not to stick it to the United States, but to defend the interests of the Russian state as he defines them. 
• Israel is quietly rooting for Russia.