It seems to be constantly forgotten that the Assad regime has signed an agreement with Iran, to help each other if one is attacked by outside forces,
which Assad has constantly called the rebel forces (and he may be right to a certain degree).
IMO, this entire kettle of rotten fish is intended
to draw the west into another war and the latest round of shelling between Turkey and Syria
is only another attempt to do exactly that. If Turkey sends troops into Syria, Iran must enter the battle, not only against Turkey, but also the rebel
forces. If Turkey is invaded by Syrian forces, then NATO must act because she's a member.
What Russia would do if its naval base on the Syrian coast is attacked, Russia will have to get involved.
Lovely stuff and all those hoping for armageddon will get their wish. Hurrah.