We haven't crossed the LAC yet.
As you said, if we really were 20km inside Indian territory, they would be shelling our troops by now.
The 20 km is just metaphorical; even on the "china's" side of the LAC is Indian territory.
Indian response has been sensible. Things definitely look under control.
It will not be wise to act, just as the enemy expects.
As I said, its no point restricting the consequences to a small tented shanty or to hurried response lasting a few days.
China has nothing to gain by upsetting India ... in the end, it may repent that its "hitlerarian" dreams ended with a soviet flag flying over reichstag.
That said, it could be "exhilarating" to be a german in 1940. What happened subsequently, is something germans are keen to forget or dissociate with.