This question has been answered many times in the past ,you could find some answers if you take the time! I myself will not waste the time answering because since these original question have been under suspect since the beginning the government propagandist have finally after years created counter theories that are designed to debunk any theory opposing the party line!
So its really up to the individual,either one is going to question the official government lies or just go back to bed and feel reassured big brother has your best interests at heart!!