If I recall correctly, one of the fears during the Cold War was due to the possible interruption of rare earth supplies to the West should an ANC government take over South Africa. The ANC was on friendly terms with the Soviet Union, and both the Soviets and South Africa were the world’s largest suppliers of these strategic elements.
The entire subject was dropped after the Soviet Union fell, and the subsequent ANC government was not as hostile towards the West as earlier feared.
It is therefore with some surprise that I read today that China now supplies 95% of the world’s rare earths. Read the story here.