The US-Turkish deal in late July 2015 was a huge gamble by both Obama and Erdogan, not when it is considered that it has proved a "game changer" in ways opposite to the intended effects. For the US it could mean being slowly dragged further into the Syrian quagmire and for Turkey it could fan Kurdish secessionism.
The decision to allow the US to use Incirlik airbase while Turkey, in return, gets to use air power to take out primarily Kurdish PKK targets looks likely to damage the effectiveness of the only force on the ground in northern Syria that has been capable of rolling back ISIS-the YPG-in which the PKK militias are part.
Given that the "strategy' of ratcheting up the Western air campaign against ISIS has thus far failed, the decision to persist with that while trying to give added and renewed backing to a "moderate" rebel force-Division 30-has backfired. Al Nusra kidnapped its members who then decided they would not fight them.
In Syria, outside the Kurdish held regions, the Sunni areas are dominated by militant jihadists imposing their will through force and terror with ISIS being only the most successful and brutal of all those supported by Saudi Arabia and the Gulf states as a proxy counter force against Iranian backed Shi'ite militias.
Erdogan has attempted to remain onside with the Masoud's Barzani's KRG in Iraq while tilting the balance against radical Kurdish forces in Syria because he remains fixated on a neo-Ottoman strategy in which Assad in Damascus has no place. He would rather Sunni militant groups-with covert Turkish backing-prevailed.
Even if the Turkish strategy in Syria has failed and only ISIS has in practice benefited that is considered now a better bet to fend off the threat that a functioning Kurdish autonomous region would pose to Turkey. Syria's Kurds believe there is no reason why they would not want to join up with those in oil rich Iraqi Kurdistan.
Kurdish nationalism is a threat not only to the state created by Ataturk but to the idea Turkey could become the most geopolitically important east-west energy transit state piping both Central Asia gas and oil from Kurdistan. Kurdish autonomy in Iraq is welcomed while Turkey is attempting to crush it in Syria.
The problem with Erdogan's gamble is that it could backfire and create the very thing he feared all along which is that the war in Syria spills across into south eastern Turkey. The KRG has condemned Turkish air attacks on PKK bases and the weakening of the YPG as it weakens their front against ISIS.
Worse still for the KRG, it puts them under pressure as they will be accused of selling out the Kurdish cause if relations and oil interests means it selling out the Kurds and enabling Kurdish civilians to be slaughtered by a resurgent ISIS. After all, there is no sign that the US and French air war alone can defeat ISIS.
Ultimately, oil interests would appear to have trumped humanitarian concerns of the Kurdish cause, something that could cost the KRG elites dearly. Having sent their troops into Syria as a way of placating Turkish fears of Kurdish radicalism within Turkey from Syria, they end up with Turkey taking action anyway.
The US, for its part, was never that concerned by the killing of minorities whether Yazidis or Kurds. Obama ignored ISIS throughout 2013 and the early part of 2014 until it surged into Iraq and threatened the oil producing regions of Kurdistan and central and southern Iraq. Only then did ISIS become a 'global terror threat'
The reason is Washington and continued to hope the FSA would knock out Assad. Only when it became clear it would have to rely on an Iranian influenced Baghdad to stem ISIS- and ensure it would not get drawn back into Iraq after withdrawal in 2011-did Obama decide to try greater diplomacy with Iran.
While the US has been at variance with Turkey over pumping Kurdish oil westwards because it undermines Baghdad and deprives it of oil revenues, there is evidence Kurdish militias are acting to try and blow up the Kirkuk-Ceylan pipeline, actions which would sabotage Erdogan's designs to make Turkey an energy hub.
Even though the PKK has officially denied responsibility so as not to threaten the KRG, the potential for the violence to intensify on the borders of a NATO state and for it to spread deep within Turkey is increasing, not least as the HDP is aligned with Kurdish groups and lauded by Cyprus and Tsipras' Greece.
As the discovery of Eastern Mediterranean gas in 2011 has caused squabbles over who has drilling rights to the gas off Cyprus, ethnic and sectarian enmities from the collapsing states created after the fall of the Ottoman Empire- and frozen during the era of secular dictatorship during the Cold War-are reappearing.