If war does start between NK and US, do not be misled into believing it will remain contained. On the contrary, it will spread like wildfire and engulf most of the Northern hemisphere. Africa, South America and possibly Australia/New Zealand may be the only safe places left, if the planet survives the massive onslaught of nuclear weapons.
It is highly unlikely that Pakistan and India would end up on the same sides. In case of China striking India with nukes, rest assured it would be a coordinated and simultaneous strike from both China and Pakistan. India would stand no chance of survival.
Pakistan can be the regional ally of China and Russia, and neutral to the US. As long as Pakistan keeps away from Israel, US will not strike Pakistan. Dying India might be able to hit Pakistan at a few places, but would not be able to wipe out Pakistan.
I hope it never comes to this, though.