Indians have been boasting in their media circus recently that they've finally managed to bypass the MTCR limit on their off-brand P-800 Oniks. If one assumes they're not lying (big assumption, I know), then the problem of defending fixed installations on the Plateau comes into play. I want to state unequivocally that if the balloon goes up, India will get its teeth punched down its throat, supersonic missiles or no supersonic missiles - but I consider China even bruising its knuckles to be a grievous loss.
An interesting idea would to deploy laser point defenses to airbases in Tibet where the thin, dry air would greatly mitigate the effects of atmospheric attenuation.