Freedom of Speech.

[nkad]

In the United States, Freedom of Speech, as defined by out Bill Of Rights, means that you can not be punished if you speak out against the Federal Government.

It does not mean you can yell Fire in a crowded theater.
It does not mean you can incite a riot.

And, it should not mean those things. For those acitivies, you should, and will be, jailed.

Just to point out a few things. Yelling Fire in a crowed theater isn't a question of free speech, but a question of morals. Therefore, I am within my right to yell Fire, when in fact there isn't. My doing so may lead to consequense, such as being told to leave, or arrest (not for yelling Fire, but rather for not obeying the property owner's request to leave the theather).

Second, your example of inciting a riot has nothing to do with free speech. However, you are corrrect that it is an illegal act. The constitution only protects our right to peaceful assembly.