Powering spaceships using compact reactors could cut down Mars transit times by more than half. The technology also has military applications, with DARPA requesting a nuclear rocket demonstrator in June 2020. The Demonstration Rocket for Agile Cislunar Operations (DRACO) project aims to create space-based assets that can move quickly within space to deter strategic attacks by adversaries. This article discusses the DRACO project and the technologies that make it possible.