A 'What If' question. Instability in Pakistan has long been a "given" and every so often it appears to slide towards the precipice, then pulls away.

I do recall, now some years ago, speculation about the (in)security of the Pakistani nuclear weapons stockpile and what should happen if nation-state, notably the military, lost both the capability and will to keep them secure. That is one issue.

Pakistan is not just a nuclear-armed state. It has a complex relationship with its neighbours, notably with India and with China and the USA. Not to overlook Saudi Arabia, especially as former and present leaders like to have long stays there or in the Gulf states - as guests.

Personally I think if the nuclear weapons, foreign embassies and resident or visiting foreign nationals are safeguarded in an emergency no-one would want to be actively involved.