PLA withdrew in 1962, as they were scared by the fast changing pace in Indian political consolidation which swerved sharply towards US. They realised US N-umbrella, plus airforce support would mean a war on scale many time bigger then the one on 38th Parallel.
India defence forces were then in transition stage from being a colonial Army to a national Army. Now times have changes, war technology has changed, the doctrines have got upgraded, and there is mega destruction.
Make more sense for you Chinkos to take legality and human rights issues seriously. Recently India had taken a decision not to make military supplies to Vietnam and other friendly countries. That policy may change.
