R. Scott Kemp, instructor of MIT's 22.04 Social Problems of Nuclear Energy, lectures on how the civilian nuclear fuel cycle connects to weapons proliferation. The session walks through uranium enrichment and plutonium reprocessing as the two technical pathways that convert ordinary reactor fuel infrastructure into a potential source of bomb material. Kemp explains why the same centrifuge cascades and reprocessing plants built for power generation can, with modification or simple repurposing, produce weapons-grade material, and why this dual-use problem has shaped decades of arms control policy. As lecture 16 in a 61 minute session, it builds on prior classes covering the fuel cycle's basic mechanics, now turning to the proliferation risks states and institutions like the IAEA must manage. The approach is technical and policy-grounded rather than political, aimed at explaining the physical and institutional chokepoints where civil and military nuclear programs overlap.