America's marketplace of ideas is threatened by social media platforms and a government security apparatus that have joined together to suppress the free exchange of ideas. In Free Speech and Turbulent Freedom, Michael J. Glennon offers an incisive defense of free speech in the digital public square. Drawing on the intellectual journey of Supreme Court Justice Oliver Wendell Holmes Jr., who shaped the modern First Amendment, Glennon argues that a lively and robust marketplace of ideas is the surest guarantor of social stability. Crisply written and lucidly argued, this timely book calls on the courts to protect the speech interests not merely of the government and Big Tech, but of all participants in the marketplace of ideas.