I have to admit that I'm something of a fan of purpose built national capitols, created from the ground up, though urban planners tend to hate them (Constantinople and Alexandria turned out OK, however).
What if the United States government decided to build one of these? After all, the Constitution allows Congress to designate a "federal district" anywhere it wants to!
What if the United States government decided to build one of these? After all, the Constitution allows Congress to designate a "federal district" anywhere it wants to!