Humanity is so fragmented that the thought of a 1 world gov't, as we currently exist, is impossible.
Mankind will, necessarily, have to be reduced in numbers first to a point that it can be governed.
There is no doubt that social but predatory man must be controlled if he is to continue to survive.
Einstein stated (paraphase) that the advent of the atom bomb made a 1 world gov't necessary if man is to survive as a species.
Humankind is headed for a disaster. It may be that which will reduce him in numbers to the point that in the next millenia a 1 world gov't will become a reality.
Man will not become extinct, but he will be regressed to the stone age where he will mutate into a human we would not recognize today.
There will be great minds that will have taken refuge underground, which will return to the surface to , again, gain control and begin the processes of adaption and progress.
Hopefully man will have learned by experience that the old ways didn't work and create "control" guided by a desire to survive as a species.