Donald Trump claimed Monday that the use of magnets was part of a plot begun by the Chinese two decades ago. During an Oval Office meeting Monday with South Korean President Lee Jae Myung, the president said he may impose a steep tariff if China didn’t give the U.S. magnets. “They have to give us magnets. If they don’t give us magnets, then we have to charge them 200 percent tariff for something, you know?” said Trump, who recently delayed putting tariffs on Chinese goods until November. In response to U.S. tariffs, China has prevented the exportation of some magnets…