Critical Rare Earths, National Security, and U.S.-China Interactions: A Portfolio Approach to Dysprosium Policy Design.

摘要

In recent decades, China has become the world's principal source of rare earths extraction, processing and manufacturing of its derivative goods. China's monopoly is partly a result of its rich geological endowment, particularly of the "heavy" rare earths that are increasingly valuable in green energy and military technology applications. The country's rapid industry consolidation, however, has been abetted by unfair policies such as export restrictions that subsidized domestic producers. Furthermore, Beijing has indicated a tight-fisted disposition, intent on reserving its rare earths for domestic consumers and preferring that trade partners "find their own sources." This dissertation examines how the U.S. can pursue a portfolio of policies to reduce American vulnerability to the supply disruption of one critical heavy rare earth, dysprosium. Intended primary for U.S. policy makers, the study first provides a consolidated narrative of the interplay of politics, economics, and geology of rare earths in general and dysprosium in particular. It then systematically evaluates the effectiveness and costs of a roster of new and incumbent policies. A new strategic planning framework leverages mixed-integer linear programming to concoct policy portfolios that maximize U.S. resiliency to dysprosium supply disruptions at given budget levels. This enables a trade-off analysis comparing the portfolios' vulnerability reduction effectiveness against their costs. This analysis culminates with a recommendation of the portfolio that balances fiscal feasibility with acceptable vulnerability reduction. The hope is that the method and research findings will also serve as a generalizable template for mitigating the criticality of other vulnerable rare earths and materials.