I am not arguing the semantics of whether Chinese action in doklam was right or wrong. But that India thwarted it very publicly by deploying troops in a forward manner. The Chinese saw it as a affront to the new super power and for months their were daily threats as the Indians are rightly viewed as a weaker power. If the Americans had taken such a step , the practical Chinese would have rationalized it away as a superior power having its way.
As someone said its all about face in some cultures and the Chinese thought they had lost face.
The nuclear question is very valid. No use making and maintaining them if the adversary is confident that they wont be used in any circumstances.
Modi has turned some of India's long held behaviors on its head by initiating strikes in Pakistan and doklam. He has introduced a unpredictability in Indian hard power which was absent after indira Gandhi.
Never be predictable.
India forced China to take one of two routes, either engage in a war with India over the Doklam drama or find another part to connect the road.
China choosing the latter isn't some Indian victory or some affront. It was a good decision. Why would China go to war over a road connection? India put military presence in southern Doklam to make sure negotiations didn't go ahead and even if some bilateral agreement is reached between China and Bhutan, India would not allow it. China chose not to engage India. Is that proof of anything other than China decided a war with India over this road connection isn't worth the trouble?
Yet Indians like to imagine it is proof India is stronger than China simply because China couldn't be bothered and rerouting the road is going to achieve the objective. What China wanted was to connect that road, it needed to use that piece of disputed land. There were other solutions and since it turned from simply negotiating a swap with Bhutan into a war with India just to connect that road, China decided on those other solutions. It has been done and the road has long been connected. And there it is.
There is nothing more to that drama but it is useful to remember that India did interject and place that choice with China, engage militarily or reroute, with China's plans disrupted wrt BRI. So I was using it previously as a reason for why China considers India antagonistic to itself and its interests. This has nothing to do with India. It doesn't threaten India, it doesn't invade or undermine India and yet India wants to mess with BRI because ... well truthfully we all know why.