With the possible exception of Punjab, which is now the top dog in the Pakistani pack, the new nations to emerge from a breakup of Pakistan likely would soon become more prosperous as well as more free, leaving them better off. This breakup of the Pakistani federation would almost certainly be preferable from the West’s perspective as well.
Under the status quo, the monstrous hybrid that is Pakistan for decades has been one of the greatest forces for instability in the world. Apart from its role as a breeding ground for terrorism, Pakistan has been the single biggest proliferator of nuclear weapons technology, its A. Q. Khan network having made or helped make nukes available to North Korea, Iran, Libya and Iraq under Saddam Hussein.
In dealing with a Pakistan that has careened from one unstable government to another, most of them dictatorial and with no genuine national interest, the West has had no effective basis for diplomacy apart from bribes, aimed at securing short-term goals, in the form of foreign aid and military hardware. Once Pakistan is broken up into entities with true and distinct national interests, grievances that give rise to strife and terrorism would abate and the problems the West now faces in Pakistan would become more manageable.