Science for society

Rare earth elements (REEs) are strategic resources and vital components of many technologies, especially those key to the low-carbon energy transition (i.e., wind turbines and electric vehicles). There is an unvalidated perception that REE supply is heavily concentrated in a handful of nations, particularly China. This assumed threat to REE supply chain security has raised concerns, particularly in the United States, and has led to domestic resource exploitation and even national alliances, which could have undesirable socio-environmental ramifications. A dynamic material flow analysis, which can trace REE flows across global networks from resource mining to product sales, reveals that between the years 2000 and 2022, the United States has, in fact, become a net exporter of REEs, with China as its largest customer. The growing interdependence of REE trade between China and the United States has stabilized rather than disrupted global REE supply chains, benefiting both importer and exporter alike.

Summary

Rare earth elements (REEs) are vital to the development of low-carbon technologies. There are rising concerns in the United States and elsewhere about REE supply chain stability and risks given the unvalidated perception in the heavy reliance of China, by far the largest REE supplier. However, the relationship between key countries at different stages of global REE supply chains remains unclear. Here, we use a dynamic flow analysis to explore supply dependence between the United States and China by tracing REE flows from mineral mining to market between 2000 and 2022. Our results indicate complementary and cooperative US–China interactions, especially after 2018 when the United States became a net exporter of REE and China’s largest supplier, and China became the largest importer of the US REEs and manufacturer of REE-enabled low-carbon technologies. This intensifying interdependence stabilizes REE supply chains and highlights the importance of cooperative REE trade networks.