After being the target of of several cyber operations over the last decade, the United States is in a mood to fight back. But there is little agreement about what to do, and how far to go. The Department of Defense has pledged to “defend forward” in cyberspace, and U.S. Cyber Command is committed to “persistent engagement” against U.S. adversaries. Critics, however, warn that these steps create new risks in a domain already fraught with uncertainty. The debate is also playing out in Congress, where the Cyberspace Solarium Commission is currently weighing different options.