In the middle ages, the structure that best defined and captured the spirit of a city was its cathedral. Think for a moment of Chartres or Notre Dame de Paris--these were enormous building projects indirectly funded by the local population. After many years of construction, an edifice was in place that, in some respects, was that city.

These days we don't build cathedrals. These days we create elaborate and expensive airports to express the spirit and sensibilities of our cities. Airports are designed so that even on a half-hour layover you get some feeling of what the city is about. Anyone who's flown in or out of Las Vegas or Detroit can confirm that.

Airports are our new cathedrals.