China's Rare Earth Embargo Against Japan (2010)
Following a territorial dispute over the Senkaku Islands, China halted rare earth exports to Japan for approximately two months. Japan, which sourced 90% of its rare earths from China, saw its automotive, electronics, and defense industries thrown into panic. Prices for some rare earth elements rose tenfold within a year.
Japanese companies stockpiled rare earths, exacerbating a price bubble that lasted over a year. China denied implementing a formal embargo.
Japan invested heavily in alternative suppliers, backing the emergence of Lynas (Australia) and Malaysian processing facilities. Tokyo pioneered recycling and substitution technologies that reduced rare earth dependency by 50% in some applications.
The 2010 episode proved China would weaponize mineral supply. It also showed that diversification is possible but requires a decade of sustained investment—the timeline the current US alliance must navigate.