India has much better way than China to take care of China.China's Missile no longer a problem for India since that gap is closing fast.By 2020 Agni V and in development Agni VI,Nuclear Submarine, atleast 3 air craft carrier,strike corp,all 48 warships in construction,jets,IRNSS Constellation,5000 km+ BMD shield,5000km K-4 SLBM,may be ASAT or even much criticized LCA Tejas bu a advanced one to be in India's arsenal.All these are becoming reality successfully one by one just take time wait and watch.With Agni V China officially in the range of India.And you talk about Brahmaputra and also happily gave UN figures but just dare it.Brahmaputra is a international water,China can't do any thing to Brahmaputra just like Indus where India is constructing dam only after pakistan fails to win or looses its case in international tribunal therefore India is in no violation of International treaty on water but stopping water will be be a gross violation of the same UN charters as you mentioned which then may prove costly for beijing.