[caf]

I'm aware of the Sino-Indian border war, but fighting skirmishes in the border region is not at all the same thing as long-running, high intensity combat deep into the opponent's territory. There's a reason why China unilaterally withdrew back to the pre-war line of control afterwards - it's just not feasible for them to take and indefinitely hold large chunks of Indian territory. The same applies to India in reverse.

This is important in the context of strategic nuclear weapons, because the only situation that would justify using such weapons is when national survival is at stake - the risks are just too high otherwise. National survival isn't threatened by short-lived border skirmishes.