How does the author try to persuade and shape public opinion?

Ray Bradbury tries to shape culture by satirizing elements he finds troubling. In Fahrenheit 451, the big issue is that people are not willing to think critically about their lives or the world. It goes beyond people just really loving television. The content on those televisions are the most vapid sort, requiring no real thought. They consume mindless programming and try their best to never think about unpleasant realities, such as the war.
The censorship of books is troubling in and of itself, but what Bradbury does to hammer the horror home is that the majority of the general public does not appear disturbed by this. Indeed, many characters, including Montag at the beginning, don't even understand why anyone would want to save books. For Bradbury, the moment people stop prizing such freedoms is when society will really be in trouble.
By showing how hollow such a world is, he is warning his own society that such a future could be theirs someday if they do not reassess their attitudes about critical thinking and freedom of speech.