Which they can do, once you get over a very high bar indeed.
We have literally seen the Supreme Court protect speech advocating for violence against the Government.
>Brandenburg v. Ohio, 395 U.S. 444 (1969), was a landmark decision of the United States Supreme Court interpreting the First Amendment to the U.S. Constitution. The Court held that the government cannot punish inflammatory speech unless that speech is "directed to inciting or producing imminent lawless action and is likely to incite or produce such action".
Specifically, the Court struck down Ohio's criminal syndicalism statute, because that statute broadly prohibited the mere advocacy of violence.
