Although personally I don't like the idea of blackmailing innocent population with water but about China, let me tell you couple of facts.
China is already diverting water from Tsangpo river.
An excerpt from wiki (https://en.wikipedia.org/wiki/Zangmu_Dam)
After denying the existence of a plan they have changed their stance to "only a small dam" and slowly they will construct more.
As for diverting indus by China, one thing will be certain. Pakistan cannot blame india any more cause it would be china stopping the water flow.
Chinese are surreptitious people who were better under japanese rule.
You better search for wind current directions across china and take back your words !
You must be an idiot by citing the zangmu dam. Reported your insult on Chinese people. Are you not an Indian decendent who is still licking your British masters?