President Donald Trump’s demand that Seoul hand over $350 billion in cash could devastate South Korea’s financial markets and economy. In July, Korea agreed to invest $350 billion in the U.S., in exchange for Washington setting a 15% tariff rate. But not all the details were spelled out at the time, and both sides have been in negotiations to finalize the deal, with tensions ramping up lately. Commerce Secretary Howard Lutnick has insisted Korea abide by terms similar to what Japan accepted, including th ...