American journalist and policy analyst Emily Parker describes how the Internet is a powerful tool not just for free speech, but for collective action in countries where mass demonstrations are quickly shut down or banned outright. Chronicling internet activism in Russia and China, Parker tells us that online, activists “know who their comrades are,” a luxury they don’t have access to offline. Parker knows that not everyone on the Internet believes in the ideals of freedom and human rights—especially the online presence of authoritarians—but is optimistic about the power of the Internet toun-muzzle even the most repressive of authorities.