It doesn't have to be, but it probably will be. I'm in Chicago and even our second airport, Midway, is showing signs of pressure. I can think of a handful of ot

It doesn't have to be, but it probably will be. I'm in Chicago and even our second airport, Midway, is showing signs of pressure. I can think of a handful of other second tier airports in major cities in similar positions. I think this is going to become a very heated topic over the next 25 years. The general public has been groomed to believe that cheap airfare on a several-hundred-million-dollar vehicle with incomprehensibly good safety standards is a birthright, so when the cost of air travel starts going a lot higher, people are going to freak out. We can make all sorts of tweaks to alleviate the problem (load efficiency, bigger planes, more seats/plane, longer hours of operation, etc) but at some point the inherent limits of a fixed number of runways, gates, and slots is going to catch up to us, and that's when the price of a ticket for many particular routes is going to go vertical.