>Would you accept that most Americans believe what their government tells them?
Often, but not always. I think Americans will believe what they're told not because they believe the government is never wrong but because they believe what the news tells them and they simply don't care enough to dig deeper. Americans also tend to believe whatever confirms their existing biases. I suspect this is not a uniquely American problem, though.
> but when the head honchos of the US "defence" forces, the Secretary of State, and the President of the United States stands in front of the nations media and talk about the foreign bogeymen who're out to get them, would you accept that most Americans believe them?
Even at the height of the post 9/11 paranoia and the Iraq war, there was plenty of skepticism and criticism of Bush's actions. Some (admittedly many) Americans thought Bush was a hero (and still do,) and others thought he was an idiot who was playing out a power fantasy in the Middle East. So it's not really the case that the whole country swallowed the government's arguments hook, line and sinker.
>Then you have the Fox News and dozens of right wing radio talk shows pounding on the same drums...
The thing with right-wing talk radio and Fox News is it's designed to preach to the choir, and it does, and the choir is large and boisterous, but it's a laughingstock to a lot of people as well. Is it effective propaganda if it only works on people who shared its biases to begin with?
To paraphrase Obi-Wan Kenobi here, what you're saying is true, but only from a certain point of view, and a narrow-minded view at that. As with any population of this size, pinning it down to any one political stereotype is difficult - our lunatic fringe is bigger than some countries.