The Middle East was the arena where the Ottoman-Safavid rivalry played out for over half a millennia all the way up to the beginning of the 20th century. The prospect of the birth of a New Middle East finds the two regional powers jockeying for leadership. Arguably, there are third parties - Western powers on the whole and some among Arabs - who may actually hope to gain out from a replay of the historical rivalry in the contemporary regional setting, which by common reckoning is working to the advantage of Iran's rise.
The sudden Turkish belligerence toward Syria has a complex backdrop. No Arab state was more anti-Turkish than Ba'athist Syria. In the Syrian folklore, Ottomans are cast as villains, and just below the surface lies a territorial dispute dating back to 1939 when Turks annexed Hatay province from Syria. This is also where the hidden meaning of the Turkish seizure of Iranian aircraft carrying weapons en route to Syria probably lies.
Again, Turkey has been reaching out to Hezbollah and Hamas, bypassing Syria's (and Iran's) claim to be their interlocutor, in an effort to enhance its regional credentials and burnish its standing with Saudi Arabia and the other Gulf Cooperation Council (GCC) states.
The GCC states, on their part, regard it a good thing that Ankara is willing to shoot across Tehran's bow. Unlike the case with Iran, whose objectives vis-a-vis Hezbollah and Hamas are viewed in zero-sum terms by Saudi Arabia, Turkey's efforts to advance its political status are not perceived as aimed at threatening or marginalizing Riyadh's interests.