It is equally possible that Russia pressured China to grant India membership in SCO because of New Delhi’s perceived shift towards the West after the US replaced Russia as India’s largest defence supplier.
It is, however, in the energy sector that China has more cause for worry. In November 2013, Vietnam offered India seven oil blocks off its coast to prospect, including three on an exclusive basis. When China objected, Vietnam and India together stridently announced India’s right to explore for oil in the Vietnamese exclusive economic zone, part of which is claimed by China. India has also announced its right to free navigation in the South China Sea, thus ignoring China’s claims to it. China can ill afford to have an antagonistic India in its west, especially one which is growing ever closer to the West, when it needs to concentrate on events in the East and South China Seas.
Essentially, China stands to gain more than it loses by withdrawing its opposition to Indian membership in the SCO.
Finally, it is necessary to attempt to discern how membership in the SCO might benefit India. Given India’s chronic shortage of energy, membership in the SCO, especially if Pakistan and Iran also accept membership, will pay particularly rich dividends. As noted previously, the Russian-Chinese oil and gas pipelines could be extended to India. This will have the obvious benefits of enhancing India’s energy security by diversifying its sources.
If Pakistan could neutralise these two threats, it could itself move away from the verge of becoming a failed state and allow the government to formulate foreign and security policy, as it rightfully ought to do.