The Bridgegate scandal has yet to take down New Jersey governor Chris Christie (though it probably hasn't helped his 2016 chances), but in an unexpected twist, it indirectly sparked the resignation of a handful of top United Airlines executives. Jeff Smisek, chairman and chief executive, Nene Foxhall, executive vice president for communications and government affairs, and Mark R. Anderson, senior vice president for corporate and government affairs, stepped down on Tuesday amid a federal corruption probe into whether the airline launched an unprofitable Newark to Columbia, South Carolina, flight solely for the benefit of the Port Authority of New York...