On Dec. 26, 2004, Mark Weingard awoke to find gigantic waves rushing toward the bedroom of his beach house in Phuket, Thailand. Weingard raced to the roof, where he looked on as the Indian Ocean tsunami swallowed the contents of his home.

By the time the sea subsided, about a quarter of a million people were dead; many bodies were never recovered. Weingard, thankful that his home had been built on stilts (albeit for aesthetic rather than safety reasons), looked to the sky. “What do you want me to do now?” he remembers asking.

As a teenager, Weingard honed his leadership skills in the Jewish youth organization B’nai B’rith. At 19, he moved to London, where he eventually landed a job at Chemical Bank (which later became part of JPMorgan Chase & Co. (JPM)). By 29, Weingard was a top trader; by 32, a multimillionaire…more.