Why then cannot South Block see that?
Well if you try to ask a person in panic or extreme emotional state (like anger) why he is doing something, you will get your answer.
I am a trained rescuer diver, one lesson is that victim in such state is not rational and has lost capability of logical thinking, to be more precisely, they don't think. It is better to keep distance from them if the rescuer is not able to physically restrain them or avoid being grabbed by them than trying to save them, that will make two dead divers than only one.
This is not to say that Indians as a whole have lost their mind. But they (the nation as a whole) do see themselves as a victim of the 1963 border war with China and being humiliated in front of the world, until that mindset is changed among absolute majority we have to accept the fact that they don't see how you see it regardless how reasonable your thought is.
One lesson that I learned from my own life (many failed experience
) is that when dealing with people, what one say is less important (or not even matter) than what ones words sound like in other people's ears. Perception is more important.
Only time can change this. But hey, India won't and can't stop China to build roads around her, there are many countries in south Asia who want to benefit from the initiative. Indians may change their minds faster when they see the benefit from her neighbors.
