Verified Defense Pro
If India looked like it was going to overrun Pakistan, the Pakistanis would probably go nuclear. What's the point of having a nuclear arsenal if you aren't going to use it when your country is in military and strategic extremis with the survival of the nation at the it's most perilous.True, but I think the scenario being talk about here for Pakistan involvement based on scenarios on China by passing Malaca Strait and used land transport through Central Asia and Sea Lane toward Pakistan ports to transport oil imports to China Interior.
The safety on that routes can be compromise by India, but for Indian to compromise that route will means they have to pacified Pakistan first.
India can pacified Pakistan, there's no doubt in there. However to do that, they have to commit most of their forces.
As India pretext to pacified Pakistan in this scenario is for compromising Chinese routes, then China will come to equation. India simply can't afford to take both Pakistan and India in same time.