Near the beginning of the complaint that the Justice Department, five states, and the District of Columbia filed this week in an attempt to halt the merger of US Airways and American Airlines is a sentence that cannot help but make a person stop and think. "Since 1978," the assembled attorneys write, "the nation has relied on competition among airlines to promote affordability, innovation, and service and quality improvements." How's that been working out for us? Well, there's definitely been innovation since the deregulation of the U.S. airline industry during the Carter years — the proliferation of hub-and-spoke operations that funneled most traffic through a few wildly overcrowded airports; the rise of no frills, point-to-point competitors (most notably Southwest) that succeeded precisely by avoiding those airports; and of course the advent of seat-back TVs and blue potato chips on JetBlue. Beyond those seat-back TVs and the jokey Southwest flight attendants, though, there have been few service or quality improvements of the sort that flyers can actually notice. And while we've been seen lots of reports over the years proclaiming the huge cost benefits to consumers of airline deregulation, and the great democratization of air travel that has resulted, there's recently been a revisionist interpretation of the data pointing out that fares were dropping and passenger numbers increasing faster before deregulation than after. Get the full story at Harvard Business Review