There is not going to be war unless we see another 26/11. Which if it were to happen, would mean Pakistan would be heavily sanctioned and isolated. Even then, it will be a limited engagement ( mini war), and there is no chance of Pakistan using any nuclear weapons because of the limited nature of the engagement.
There is only one way for both countries and most importantly for Pakistan to get back to being economy focused and successful. That is accepting current boundaries.
I've had this discussion a hundred times with different people in different governments. Sixty plus years = statute of limitations has expired.
This thing has run its course.