"Congress shall make no law respecting an establishment of religion or prohibiting the free exercise thereof; or abridging the freedom of speech, or the press; or the right of the people peaceably to assemble and to petition the government for a redress of grievances."
Letting citizens freely express their minds may result in uncivil reactions when trying to maintain a civil society.
In modern day citizens wonder if the first amendment should cover things like pornography, flag-burning, hard-core rap lyrics, tobacco advertising, and hate speech.