Any speculation about Putin's aims in the Middle East must also take into account his operations in and around Ukraine.
Why does he want to build a runway for Airplanes in Syria ? Why does he want Russian warships in Syrian ports ? Why did Russia and China vote against all proposed UNO resolutions since 2012 which tried to put pressure on Syria and President Bachar Al Assad ?
The answer must be that Putin wants to have a stronger base in the Middle East for the Russian Fleet of ships which are mainly anchored in the Black Sea area.
However, Putin also wants to join any war against the Islamic State Extremists in order to protect Russia. Syria would be a good base for Russian troops, which could then also protect Syria !
Up to now Putin has avoided fleeing Syrian Refugees trying to migrate into Russia, but Refugees fleeing into Russia from Ukraine have always been welcome !
When the war in the Middle East is over, Putin will want to maintain a solid presence in the Middle East, but he will also insist that Crimea, which he illegally snatched back from Ukraine, should be officially recognised as being Russian ! Yet he also desperately wants to free Russia from the Sanctions which have been imposed by the West !
Deciding the spoils of the War in the Middle East will be like another "Yalta Settlement" in 1945 !
Putin will claim not only Crimea, but at the same time also try to hold on to certain Rebel held areas of Eastern Ukraine on the Russian border.
In this game of Political Chess, the best move by the West would seem to be to fast-track Ukraine into the European Union !