Vladislav Klyushin was having, by any measure, an awful day. The judge in his case had brushed aside his lawyers’ arguments and his friends’ appeals for leniency. She handed down a tough sentence: nine more years in US federal prison, on top of an order to forfeit a fortune, $34 million.But if Klyushin was upset about the ruling, he didn’t show it. The then 42-year-old tech executive from Moscow seemed upbeat—quick with a smile on his pinchable cheeks and unerringly polite, just as he had been d...