>>108>Will it escalate?Not between Turkey and Russia. The sanctions response is a farce to have President Putin save face. Turkey owns the Black Sea and its allies own enough of the Caspian to contest Russia's missile platforms there.
Even if Russia sees the Assad regime as a critical national security issue, they will not continue to test the Turkish border or those of NATO countries. Turkey probably feels as strongly about its non-isis rebels and any provocation along those lines will quickly cascade into a situation where they have no control. Russia will not risk losing its 90% non-isis air campaign in the rest of Syria.
This is, on the other hand, the start of a wider escalation. After the next US president or sooner, there will be a no-fly zone in Northern Syria that will exist specifically to stop regime and Russian bombings. Turkish aircraft and trigger pullers will feature prominently in that no-fly zone. It would behoove Russia to not over-step now or then.
>Russian sanctions on Russia?You're right, they will hurt Russia most of all. For now, though, their ghetto-rich on their national surpluses and have about another year (all other things equal) of having their cake.