The intensifying focus on terrorism, and on Islamic State in particular, poses a fresh challenge to the greatest American contribution to the theory and practice of free speech: the clear and present danger test. In both the U.S. and Europe, it’s worth asking whether that test may be ripe for reconsideration.
As developed by Justices Oliver Wendell Holmes and Louis Brandeis in the first decades of the 20th century, the clear and present test ensures strong protection for almost all speech, forbidding the government from regulating speech unless the danger is both likely (“clear”) and imminent (“present”). If a person were to say “The U.S. government should be overthrown” or “The more acts of terrorism, the better,” or “All Muslims should join ISIS,” she couldn’t be punished unless those statements were likely to produce imminent lawless action.