The US government finally got its metaphorical hands on Do Hyeong Kwon, the 33-year-old Korean national who built a financial empire on the cryptocurrency Luna and the "stablecoin" TerraUSD, only to see it all come crashing down in a wipeout that cost investors $40 billion. As private investors filed lawsuits, and as the governments of South Korea and the United States launched fraud investigations, Do Kwon was nowhere to be found.