Behind Every Great Fortune
...is a great crime*.
Fred Koch, according to Jane Mayer's Dark Money, made his big bucks building refineries for Stalin and Hitler. Koch, a founding member of the John Birch Society, came to regret his association with Stalin, but he liked Nazi Germany enough to hire a Hitler loving German nanny for his children. He also showed a fondness for pre-WWII Italy and Japan. The refinery he built for Hitler was the prime source for the high octane aviation gas used by the Luftwaffe, and the destruction of the refinery cost the lives of hundreds of allied airmen and tens of thousands of Germans on the ground.
Gramps Trump made his fortune another old fashioned way. According to Wikipedia:
Trump made his first fortune operating boom-town hotels, restaurants and brothels in the northwestern United States and western Canada.
The apple doesn't fall ...
*Balzac via The Godfather.