The freedom of speech is not a written human right. But do you want to know what is? The freedom to feeling safe and respected, the right against bullying, violence and harassment. By having the government monitor and clarifying what we are allowed to say, it is merely helping us to stay in line with the human rights such as these, and not being free to throw the insults, discriminative comments and disrespectful remarks we may feel like saying.
The governments of the world must not be allowed to define freedom of speech on their own terms, or there will be no freedom of speech whatsoever. Freedom of speech is very much a right to criticize and ultimately challenge the government, and this is a right that has been gained in spite of government.
The concept of restricting free speech violates the principle of freedom of speech at all and means that freedom of speech really does not exist. Freedom of speech was made a broad concept in order to prevent government interference in communication, and for the government to restrict or "further define" free speech would be to strip one of the most fundamental American rights.