TOKYO -- Japan's curbs on semiconductor material exports to South Korea have created an international fuss. But if South Korea's economy were strong, the fuss would not amount to much.
In 2011, after a big earthquake, tsunami and triple meltdown struck Japan's northeast region, Mitsui Mining & Smelting shut down one of its plants. At the time, the Japanese company controlled more than 90% of the market for ultrathin copper foil, which is essential to smartphone production.
