See also the related NYT article: What to Know About China's Halt of Rare Earth Exports https://news.ycombinator.com/item?id=44236545 (10 hours ago)

The problem extends outside the military to the car industry and anywhere strong magnets (and other rare earth end products) are used.

>By Keith Bradsher, who has covered the rare earths industry since 2009, and reported from the mining hub of Baotou, China.

I would venture that Bradsher knows more about this subject than most journalists. 16 years!