who deserves a good deal of the credit for it, is a hero of air travel. Last week, writing about the Justice Department's move to block US Airways' planned merger with American Airlines, Mother Jones blogger Kevin Drum highlighted a novel counterargument. Mr Drum says that it is still "an open question whether deregulation was such a boon for the flying public in the first place," and points to a 2012 article by Phillip Longman and Lina Khan.

In that piece, published in the Washington Monthly (where I was once an intern), Mr Longman and Ms Khan argue that airline deregulation has slowly killed mid-sized airports and the cities that depend on them. Here's the thesis:

Over the years, most Americans have adopted a pretty standard line about the results [of airline deregulation]. On the one hand, complaining about the indignities of flying—overbooked, late, or cancelled flights; surly flight attendants; and, more recently, terrible in-flight food service and high fees for checked baggage— has become a staple of American life, much like complaining about Internet providers or health insurance companies. On the other hand, we’ve told ourselves, at least the increased competition has made air travel cheaper. And at least most of us can still get where we need to go by air.But now we find ourselves at a moment when nearly all the promises of the airline deregulators have clearly proved false. If you’re a member of the creative class who rarely does business in the nation’s industrial heartland or visits relatives there, you might not notice the magnitude of economic disruption being caused by lost airline service and skyrocketing fares. But if you are in the business of making and trading stuff beyond derivatives and concepts, you probably have to go to places like Cincinnati, Pittsburgh, Memphis, St. Louis, or Minneapolis, and you know firsthand how hard it has become