Someone once said that a persons beliefs is what forms their perception of reality. These days a persons beliefs are formed mostly by a form of mainstream media. Therefore it wouldn't be at all out of line to question the credibility of the information we receive every day. One of the key pillars to a functioning democracy is a free and impartial media. The world is attempting to globalize and International news coverage is actually decreasing. In many countries journalists are threatened by the power holders with censorship, beatings, or even death for reporting issues that might be controversial or not in the immediate interest of them.
"A popular government without popular information, or the means of acquiring it, is a prologue to a farce or a tragedy, or perhaps both." James Madison couldn't have said it better. What I take from that is that without censoring the things that get censored the government might not be as powerful as it is or even exist. Unfortunately, I think that is very close to the truth. There isn't a government I've heard of that tells their people everything. The corruption in this world is too high for us to even be able to handle if we knew about it, and the really sad part is that the majority of Americans or most other races for that matter would agree on the "fact" that overall human nature is well-meaning.
All is fair in love and war right? In war, the "good guys" and the "bad guys" can often both be guilty of misleading their people with subjectivity, exaggerations, distortions, inaccuracy, and fabrications in order to receive support and legitimacy. It's a proven fact that propaganda works, in many cases it's been able to rally many people to support a cause at the cost of exaggerating and/or lying about the issues. Usually the government (or whoever is trying to gain support) will try to make the "benefits" of their actions appeal to as many people as possible whether or not it's the truth and then support it with rhetoric about the righteousness of themselves.