"Freedom of speech" is understood to mean freedom to express any opinion or idea. It doesn't literally mean freedom to speak arbitrary words. There are many, many illegal acts which you can commit by merely speaking words, like fraud, blackmail, harassment, etc.

The buck stops where the Supreme Court says it does. They are the ones who get to decide the meaning of the words in laws and the Constitution. As a side note, the first amendment does not bind the states from creating laws that limit speech as it is written that 'Congress shall make no law...'. This comes from the Doctrine of Incorporation[1] based off of precedents set by interpretations of the Fourteenth Amendment. Now there's an amendment with an interesting history. [1] http://en.wikipedia.org/wiki/Incorporation_of_the_Bill_of_Ri...

Here's some details on the first amendment and what is and isnt protected under the constitution:

http://debmcalister.com/2011/06/03/7-things-you-cant-claim-f...

Some things not protected:

1 - Hate speech

2 - Speech that incites violence or encourages the audience to commit illegal or dangerous acts.

3 - “Material support“ to domestic or foreign terrorist groups,

4 - Public speech made in the conduct of their duties by public employees.

5 - Slander, libel or defamation.

6 - Publishing confidential, trade secret, or copyright material

7 - True threats. Like many other areas of First Amendment protection, context, target, and intent matter in determining what is or is not a true threat. Some threats are always illegal — any threat to the President of the U.S., for example.

While the constitution is broad in its definition of what is free speech, local, state and the federal government still have some say in what they considered to be covered by the first amendment. Even in some cases it's arbitrary such as the Westboro Baptist Church hateful protests are legal, while a kid burning a cross is not.

> It takes precedent over any law, legal theory, precedent, tradition, etc.

The framers were (mostly) lawyers, and wrote the document against the background of English common law: http://www.libertylawsite.org/liberty-forum/why-you-cant-und....

Exceptions to the "freedom of speech" are part of the Constitution, despite not being written in so many words, for the same reason "due process" requires a presumption of innocence, even though the latter phrase appears nowhere in the document.