His long range goal is to recreate on some level Turkish dominance of the region and Sunni Islam that was lost with the dismantling of the Ottoman Empire following WWI. Assad is a client of Iran and Russia. The roots of Turkish enmity with both are centuries deep.
If this adventure puts Turkey neck deep in s#!+ and they try to invoke the NATO treaty things could get interesting very quickly.
Correct -- Turkey v/s Russia has been true since 1453 -- with the fall of Constantinople, Russia's Grand Duke renamed himself Caesar/Tsar, the inheritor of the Roman Empire. Since then, one of Russia's goals has been the retrieval of Constantinople for Christendom. This permeated Russian psychology to such an extent that even Soviet military genius Tukachevsky who was avowedly anti-Christian, still wanted to conquer Constantinople. Russia will never give up that goal -- it's part of its soul
Turkey v/s Iran dates from the 12th century when the Turkic peoples slaughtered millions of Iranis. It continued through the genocides of Timur-E-Lang and the centuries of war between the Ottomans and the Safavids.