All “freedoms” come with limits, and the freedom of speech as codified by the The First Amendment to the United States Constitution is no different. These limits are based on the following considerations:

• National security: The government can restrict speech considered a threat to national security. For example, the government can restrict speech that reveals classified information or that incites violence against the government.
• Public safety: The government can restrict speech considered a threat to public safety. For example, the government can restrict speech that incites riots or threatens to harm someone.
• Harassing or threatening speech: The government can restrict speech considered to be harassing or threatening. For example, the government can restrict speech that makes threats of violence, or that is intended to cause emotional distress.
• Defamation: The government can restrict speech considered defamation, which is the publication of false statements that harm someone’s reputation.
• Obscenity: The government can restrict speech considered obscene, which is offensive to prevailing standards of decency.
• Child pornography: The government can restrict speech that is considered to be child pornography, which is sexually explicit material involving a minor.

Note that these are just some limits to free expression under the US Constitution. The specific limits in any given case will depend on the circumstances.

It is also important to note that the First Amendment does not protect all forms of speech. For example, the First Amendment does not protect speech intended to incite imminent lawless action. This is known as the Brandenburg test.

The Supreme Court established the Brandenburg test in the case of Brandenburg v. Ohio (1969). In this case, the Court ruled that the government could not punish someone for speech that was merely advocating violence if the speech was not intended to and was not likely to incite imminent lawless action.

The Brandenburg test is a complex one, and it has been interpreted differently by different courts. However, it is generally considered a high bar that the government must meet to restrict speech.

The limits to free expression under the US Constitution are essential to protect individuals’ rights and ensure that the government does not abuse its power. However, it is also crucial to balance these limits with the right to free speech, a fundamental right in a democracy.