Don't people realize that it's probably the most important building in world history? It really does symbolize New York and America in general. It's our link to the culture of the Roaring 20's and defines the early 20th century. Every other skyscraper project undertaken in the 20th century pales in comparison because they were just attempts to build something bigger and more innovative. The ESB is one of a kind.
I always make it a point to visit at least once a year and I never felt that way about any other building. When my grandparents would tell me stories of New York in that era when I was a kid, I'd always ask them about it. It's such a powerful feeling to go there and feel connected to the great industrialism of the early 20th century and say to yourself THIS was the start of modern America right here.
If America is in shambles in a few thousand years like Ancient Rome and Egypt, and I could only pick one landmark I'd want future civilizations to get a better idea of what America was like, I'd easily want it to be the Empire State!