Four of the world’s largest Internet companies pledged to monitor, combat, and prevent terrorists from using their social media platforms to conduct operations in May 2016. One month later, Twitter, Facebook, and Google were sued for deaths caused by the Islamic State in 2015, and their alleged allowance and facilitation of terrorist communication. A growing demand for responsible and accountable online governance calls into question the global norms of cybersecurity and jurisdiction, and the very definition of terrorism. This paper explores the legislative precedent for countering terrorist communications, including the evolution of the First Amendment, communications and information law, and limitations governed by public opinion. Using legal trajectories to analyze aspects of monitoring and censorship in both past and current counterterrorism strategies, evidence of the future cyber landscape becomes clear. Cyber norms will imminently and inevitably depend on public-private partnerships, with liability split between the government and the private companies that control the majority of the world’s information flows. It is imperative for actors to identify each sector’s competing and corollary priorities, as well as their legal and normative restrictions, to form partnerships that can survive the unpredictable court of public opinion and provide sustainable counterterrorism solutions.