The Problem I have with Propaganda

I watched this movie and The End of America (2008). As it is, I am getting not getting direct testimonies for the most part. In addition, I am getting sound bites, that is, snippets of interviews and comments. You can take snippets of anything and make it up. Some of the things presented are thought provoking -- and shockingly frightening. However, how reliable is the information? Will the general public ever learn the truth and from whom?