The Pentagon has moved aggressively to establish domestic sourcing of samarium, a critical rare earth element essential for high-performance aerospace systems facing extreme operational stress. In March 2026, the Defense Logistics Agency awarded contracts to scale metallothermal processing for samarium and gadolinium, targeting a 300-ton-per-year production facility to re-establish commercial-scale domestic output. This marks a sharp departure from the past decade of supply chain passivity and reflects the strategic reality that samarium-cobalt permanent magnets operate under heat and stress conditions found in jet engines, missile systems, and spacecraft avionics where conventional rare earth magnets would fail.
Fighter jets embody this dependency at scale. A single F-35 contains approximately 100 pounds of rare earth elements distributed across thrust vectoring systems, flight control actuators, radar units, and power generation subsystems-functions that cannot be redesigned away. Northrop Grumman's B-21 Raider stealth bomber demands samarium and other rare earths for propulsion, low-observable technologies, and sensor networks engineered to zero-defect specifications. Modern aircraft electrification amplifies this constraint: narrowbody aircraft increasingly rely on starter-generators, environmental control pumps, and advanced sensor architectures where rare-earth permanent magnets provide the power density and high-temperature stability that alternative materials cannot match. NASA research has long highlighted samarium-cobalt magnets for aircraft electrical machines due to their coercivity and resistance to demagnetization in elevated thermal environments.
The supply chain vulnerability is structural and immediate. China controls over 90% of global rare earth magnet production despite holding a smaller share of raw ore reserves, commanding the entire vertically-integrated chain from mining through separation to alloying and finished magnet fabrication. In October 2025, China announced rare earth export controls that posed severe risks across energy, defense, aerospace, and semiconductor sectors, forcing U.S. contractors to face new Department of Defense compliance deadlines in 2027. Satellite constellations and advanced intelligence, surveillance, and reconnaissance platforms depend on rare earth components engineered for extreme environments ranging from deep space thermal cycling to high-radiation exposure. The production timelines for both classified and unclassified aerospace programs now hinge on whether secure, non-Chinese sources of high-purity rare earth metals materialize on schedule. Without domestic samarium-cobalt supply, defense contractors including RTX Corporation, Boeing, and Northrop Grumman face delivery delays that cascade through procurement pipelines supporting global air power, ballistic missile defense, and space modernization initiatives.