Anyone who understand warfare will realise that no large military operations can be undertaken across the Himalayas. 1962 was because there were no troops on the border and India had no clue of High Altitude Warfare! But it was a lesson well learnt and should never be forgotten!
India has defended itself four times with Pakistan since independence and not once has China intervened.
China, currently, is consolidating and is more keen to become a superpower that can challenge the US and replace the USSR as the main contender of global power. It would be an immature suggestion, apart from being a dream, that China will intervene in any conflict or embark on any wars. Her political statements, complicated that they are, requires to be understood.
Likewise, India is equally concerned about moving towards great economic and political goals to have it derailed with infructuous activities like a war!
Therefore, to believe that India or China would go to war, is quite unthoughtout a thought.
In so far as Bangladesh is concerned, the relations are not perfect and both sides are to blame.
It is in the interest of both to have good relations.
On the issue of India decimating the concept of Pakistan in 1971, it could never have come pass, had the West Pakistanis not stolen the governance of Pakistan from Mujabir because of their contempt of Bengalees as rice eating, dark, short statured people who being non martial have to be kept underfoot. The same contempt shown towards Mohajirs by roadrunner in the thread:
http://www.defence.pk/forums/strategic-geopolitical-issues/7886-face-bomber-2.html
The Pakistanis, of that time, forgot that brains better brawn!
