Well, the truth about 9/11 is in some sense already out in the open. The fact that 82% of those polled support Charlie Sheen's recent comments about the destruction of the World Trade Center and the Pentagon impact seems to indicate that this truth is also accepted by a large percentage of people. There is now so much widespread disdain for both the Bush and Blair administration that people are waking up to the fact that their elected officials are liars, crooks, and even murderers.
The biggest problem is the fact that the mainstream media are still towing the official party line in regards to the event. The major riots or other large scale mass demonstrations would only come about when and if the citizens who currently support the mainstream version were suddenly told this was not actually the truth. It is they who would feel outraged and deceived. The rest of us would simply carry an "I told you so" attitude about it all.
What would happen as a result? Bush, Cheney, Rumsfeld, Rice, and many other members of the current US administration would immediately be arrested. Leaving the country wouldn't save them from that fate, because they would be considered to have commited crimes against humanity and wanted under international law. There would be an absolute media frenzy over the event, along with public cries of "how could they have done this?" Major policitians and big name power players around the world would wipe the crocodile tears from their eyes as they state, "we need to make sure that something like this can never happen again." In time, there would be calls for an international governing body to be created which would have the power to snoop on any country in the world and tow them in line.
This is one possible way that the world government would come into being.
"Fear is the great barrier to human growth. Unknowns create fears. When these Unknowns become Knowns the fears diminish and disappear, and we are able to cope with whatever confronts us." - Robert A. Monroe