https://www.reuters.com/article/us-southkorea-japan-laborers-explainer/the-high-tech-trade-dispute-rooted-in-japans-wartime-history-idUSKCN1U31D1

Japan has tightened curbs on exports of high-tech materials used in smartphone displays and chips to South Korea, upping the ante in a decades-old dispute with Seoul over South Koreans forced to work for Japanese firms during World War Two.