One of billionaire investor Warren Buffett's biggest insurance bets just landed a role at the center of a global crisis. Chubb, the Zurich-headquartered insurance giant in which Berkshire Hathaway has built a massive position, has been named the lead underwriter for a U.S. government program to insure commercial ships navigating the Strait of Hormuz. With oil prices spiking and tanker crews refusing to sail near a war zone, Washington needs a private-sector partner with real firepower. It chose Chubb (CB ...