There will be a significant change in world geopolitical scenario in 15-20 years when China reaches parity with the US. When that happens, China will start augmenting SCO and turn it into a NATO like security alliance structure in Asia. Turkey will have the option to switch sides at that point, leave NATO and become a part of China led SCO. I believe SCO will have two main branches, one in Eurasia to the North and West of China and the 2nd in East Asia, South and East of China. This will be China's near abroad, sphere of influence, what ever you want to call it. I am not sure whether India will join SCO or remain nonaligned. My money is on India remaining nonaligned.
Both the Eurasian branch of SCO and East Asian branch of SCO may coalesce into viable Unions.
East Asian branch of SCO: ASEAN (minus Vietnam and Philippines) + Bangladesh + Sri Lanka + North Korea + South Korea (future) + Japan (future)
Eurasian branch of SCO:
Former Soviet countries that do not join EU + Turkey (future) + Iran + Afghanistan + Pakistan + Kurdish part of Iraq + Shia part of Iraq + Mongolia (future)
While China will remain the super core, the peripheral cores can be Japan, South Korea, Turkey, Russia and perhaps Iran and Indonesia, much later. The other nations will remain as semi periphery and periphery depending on their economic, growth performance and efficiency:
World-systems theory - Wikipedia, the free encyclopedia
The goal of above SCO security structure is to
- provide security, stability and a platform for conflict management
- prevent hostile outside interference and resulting destabilization
- achieve economic integration and growth
just as it is happening in NATO and EU countries, so that eventually all member countries can become similar in GDP.
In the above unions, free flow of goods is possible, but not of people and no Euro like common currency should be introduced.
The West will not like to see such a structure, but the West did not ask the rest of the world when they formed NATO and EU, so I say to each his own. And when China reaches parity with the US, the West will be powerless to see China lead such a group of nations in a structure I have outlined above.