I'm not entirely convinced Obama and Erdogan didn't do this on purpose...to fracture an alliance to really get rid of ISIS...it isn't inconceivable to me that they are protecting ISIS.
Obama's interests seem to center around protecting and defending all forms of radical Islam all over the world. Point by point to follow.
He has shown open support for the Muslim Brotherhood from day one. There are accusations that Obama has allowed members of the MB to infiltrate the White House and the Pentagon.
Obama has always been very soft on the Taliban, and has insisted on them to be viewed not as an enemy, but rather as a potential ally, against the protests of the vast majority of our political and military analysts, and even against the frenzied protests of the local people and government who would be slaughtered by them.
Obama's love for Hamas, Hezbollah, and the PLO is well known. Even though these are three of the bloodiest and most deadly terrorist organizations on Earth, both to their own people, and to the West. While Hamas was in the process of bombing Israel with thousands of rockets aimed at civilian centers in an unprovoked attack, Obama was busy yelling at Israel, not at the terrorists, for having the gall to defend themselves. He cut arms shipments to Israel, not to the terrorists, and many, myself included, believe he was looking for any excuse or pretext to attack Israel to defend Hamas.
Obama essentially gave Libya to Al Quadia on a silver platter. He had American forces fighting along with and in support of Al Quadia forces to illegally overthrow the sovereign nation of Libya with no approval from Congress, or the U.N., or our allies, or anyone else. This was a war that overthrew a nation, resulted in the death of its President, and changed North Africa and Europe forever, and it was all done by the spoken word of Obama, simply because he wanted to.
Also, after Bin Laden was killed, Obama had him buried at sea in a full blown religious Islamic ceremony.
Having said all of that, it is important to note that Obama's antipathy for Israel is famous. But, he does not care for Egypt, or Jordan, or the Kurds, all of which are relatively moderate Muslims, and are not openly hostile to Israel and the West.
So yes, it is entirely possible that Obama sides with ISIS over the Western nations. Obama may view ISIS as the victims, and Russia as the 'White Oppressor'. Whether or not Obama is ready to fight Russia to defend ISIS remains unknown. But I would not put it out of the realm possibly.