Samarium Powers Tomahawk Missile Precision Amid China Supply Squeeze

The U.S. military's Tomahawk cruise missile relies on samarium-cobalt magnets to achieve pinpoint accuracy during flight. These magnets control the missile's fins, enduring extreme heat and stress to ensure guidance systems function flawlessly over long ranges. Processed almost exclusively in China, samarium has become a strategic vulnerability as Beijing tightened export restrictions in 2025, briefly halting supplies to American defense contractors.

China's dominance stems from decades of state-backed consolidation, controlling 90% of global rare earth refining and 100% of samarium metal production. When export licenses were delayed or denied last year, firms like Arnold Magnetic Technologies in New York relied on stockpiles to keep Tomahawk production alive. This incident exposed how a single element could paralyze weapons manufacturing, prompting emergency deals with European suppliers and U.S. loans to innovative processors in Indiana.

Samarium matters strategically because no viable substitutes match its heat resistance—critical for missiles launched from hot jet exhausts or hypersonic threats. The Pentagon views this dependency as indistinguishable from energy security risks, fueling investments like the $400 million stake in MP Materials and partnerships with startups such as Phoenix Tailings. These efforts aim to rebuild a domestic 'mine-to-magnet' chain, but scaling remains years away given refining complexities.

Heavy rare earths like samarium, dysprosium, and terbium are even scarcer outside China, powering not just missiles but F-35 jets, Virginia-class submarines, and radar arrays. Ukraine's drone swarms already strain global supplies for rare earth batteries, foreshadowing intensified competition. As DFARS regulations mandate zero Chinese content in defense supply chains by January 2027, companies like USA Rare Earth are racing to deliver alternatives from Texas deposits rich in these elements.

This samarium saga underscores broader geopolitical tensions: China's layered export controls, suspended temporarily after Trump-Xi talks, could snap back, creating a 'invisible wall' for U.S. contractors. With demand surging from EVs, wind turbines, and AI hardware, securing samarium isn't just about missiles—it's about maintaining technological edge in an era where rare earths dictate battlefield outcomes.