After accusing Indian troops of crossing over the disputed Sikkim border last month, Chinese Communist Party outlet Global Times published a commentary Tuesday urging restraint by both belligerents, but warning that China was prepared to engage India in a battle for the contested land. The piece chalked up the conflict to a greater competition for economic and political dominance between the two leading Asian powers and said that Beijing would amass troops and armaments at the border in anticipation for what could turn into an all-out war.
I've noted this and there is more background information links there.
China has the edge with the ability to reinforce more rapidly and with a better air force than India has to provide top cover.
India recognizes China's edge there and is working to build up their troops and infrastructure in the northeast to match China's capabilities. That's a positive for India, eventually.
But India's dysfunctional arms procurement bureaucracy seems to be the most effective Chinese air superiority asset so far.
India would lose in a serious fight given the balance of forces there.
On the other hand, if China pounds on India over this, it will likely alarm a lot of China's neighbors. That might cow them. Or it might alarm them enough to keep arming up to better resist China.
And India could retaliate by forging closer ties to Taiwan, America, and Japan, for example, to distract China from the land border with India.
It might even alarm India's arms industry enough to be more effective.
So it is more complicated than just the local balance of forces and the location of an obscure border line.
UPDATE: More from the BBC which says that despite the escalating tensions that war is unlikely. They expect a continued stand-off.
Perhaps. But China has the edge and might want to "teach India a lesson" and put them in their place. China may not be able to challenge America for global dominance but China can challenge India for pride of place in Asia. And China has the advantage in being able to deploy forces to the theater.
India on the other hand is pining for revenge for the humiliating loss in the 1962 border war. And to add more fun, given India's need to maintain their close relationship with Bhutan as a buffer state, India might need to fight a war to preserve that tie even if the likely outcome is a loss. If India won't fight over Bhutan, will Bhutan shift to alliance with China?
And if a tense stand-off continues, one spark can make this very hot very fast.
UPDATE: And let me add that because each side has nukes, both sides have incentive to rapidly grab a chunk of land while opposition is weak, dig in, and rattle nuclear sabres to keep their limited gain.