"For the first time ever, the United States homeland cannot be taken for granted as a secure rear area against non-nuclear attacks."So argues Steve Rosen, professor emeritus of government at Harvard, in a bracing Conversation on the radically new security environment created by AI, precision strike weapons including drones, and cyber capabilities. Because these technologies give a distinct advantage to the offense, Rosen contends the US must "think about ways of similarly putting adversary assets at risk." He also explains what twentieth-century history can teach us about mobilizing the nation's resources in government, industry, and the wider community of experts, to counter critical threats to America and the free world.