Promoting the rule of law in Afghanistan has been a major U.S. foreign policy objective since the collapse of the Taliban regime in late 2001. Policymakers invested heavily in building a modern democratic state bound by the rule of law as a means to consolidate a liberal post-conflict order. Eventually, justice-sector support also became a cornerstone of counterinsurgency efforts against the reconstituted Taliban. Yet a systematic analysis of the major U.S.-backed initiatives from 2004 to 2014 finds that assistance was consistently based on dubious assumptions and questionable strategic choices. These programs failed to advance the rule of law even as spending increased dramatically during President Barack Obama's administration. Aid helped enable rent seeking and a culture of impunity among Afghan state officials. Despite widespread claims to the contrary, rule-of-law initiatives did not bolster counterinsurgency efforts. The U.S. experience in Afghanistan highlights that effective rule-of-law aid cannot be merely technocratic. To have a reasonable prospect of success, rule-of-law promotion efforts must engage with the local foundations of legitimate legal order, which are often rooted in nonstate authority, and enjoy the support of credible domestic partners, including high-level state officials.