Don't you think that a conspiracy this huge, would be revealed at some point? I mean, what proof do you have that there is a conspiracy anyways? Oh, and while we are at it: Why would the government try to trick us anyways? What are their motives? Personal gain? Well, I don't see how profit fits into this whole theory.
Remember Lincoln's words:
You can decieve some people all the time.
You can decieve all people, for some time.
But you can never deceive all people, all the time.