Seeing Turkey move from its traditionally mostly secular government toward a more Islamist-influenced gov't the last many years, and considering how they've gotten closer to Russia I'm surmising that they may be entertaining notions of being the head of some sort of reconstituted Ottoman Empire allied to Russia and the rest of the TAA/SCO countries.

I don't know if them bailing on NATO will cause the break-up of the organization, but it will definitely shake it to its core.