I like to think of it like this. Propaganda has always been a tool to sway the public mind. In the past it wasn't that powerful due to its limited scope. With the invention of the printing press and the eventual distribution of the newspaper, propaganda became much more powerful in its ability to control the hearts and minds of the masses. For example, Napoleon Bonaparte once said, "Four hostile newspapers are more to be feared than a thousand bayonets." Even in his time, the media was something to be feared.
Now imagine the power of such a media multiplied by like 1,000,000, perhaps even more, and you can get an idea of the power of the modern mass media over the minds of people. The primary culprits are television and Hollywood, but it exists everywhere. Books, magazines, newspapers, radio, internet--you name it. Any form of communicating information can be used toward the means of dispersing propaganda or disinformation.
Now, I am not sure if the people on this forum are aware of it, but the mass media is nearly entirely owned by a certain group of people. These people use the media not only for the purposes of political propaganda, but also to enforce the law of political correctness, to reinforce secular/leftist beliefs about reality, and to promote anti-Christian and anti-Western sentiment. One needs but turn on MTV to see what the youth of today are being fed to know something is not right.
It is no wonder the West is in such a sickly, degenerate state. It is no wonder that the youth are being led toward culturally Marxist views of the world and atheism. Couple the general message of the mass media being simultaneously promoted in public education and higher education, and you have whole generations of people who are, quite literally, brainwashed. Social engineering has become an art, and most of the West is subject to it.