Two weeks ago, on a sparkling spring morning, we went trawling along Florida’s coastal waterway. But not for fish. We parked a 17-foot motor boat in a lagoon about 800 feet from the back lawn of The Mar-a-Lago Club in Palm Beach and pointed a 2-foot wireless antenna that resembled a potato gun toward the club. Within a minute, we spotted three weakly encrypted Wi-Fi networks. We could have hacked them in less than five […]