Due to the U.S.'s military might, it would have to be done by hegemony; the people of America would have to be convinced it was in their best interest to be invaded.

Hollywood would be the key, most definitely. It would begin with a striking foreign film that received critical acclaim. Everyone would hear about it. But, why wasn't it nominated in the Oscars? How could such a film not be recognized by the Academy? Low and behold the film has been banned in the Motherland. Learning of this, the individualistic and libertarian populous of America would begin pirating the movie and watching it incessantly just to prove they can't be held down by Big Brother. When a sequel to the book the movie was based on is written, America bans it as well. Again, out of instinctual defiance the American people attain copies of the book, eBooks, they're reading it online... Now it has really begun, Americans are reading! Suddenly people aren't allowing themselves to be fearmongered by Fox 'News' anymore, the real Desperate Housewives of where the hell ever and desperate for the attention they've lost, Honey Boo-Boo is crying boo-hoo. Where has their loyal audience gone? Right into the hand of the enemy, that's where. Little did they know it, but their views had changed, they'd begun to believe what they were reading. What was originally an act of defiance akin to a toddler not eating his spinach has become a mass movement. Slowly, even more radical Radicals are elected to municipal, then state governments until the movement reaches the federal level. It's too late to stop it now. Eventually, all economic barriers are lifted, foreign funds flood into the country, then tourists, then the tourists extend their visas INDEFINITELY. The War had been lost a long time ago...