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There are a thousand hacking at the branches of evil to one who is striking at the root.
—Henry David Thoreau, 1854
Going faster seems to be a central part of human development. As little as three hundred years ago, the fastest you could expect to go was a few tens of miles an hour, aboard a fast clipper ship with a stiff wind behind you. Now, we must expand our view to things such as the fastest achievable speed while remaining in the Earth's atmosphere -- perhaps fifteen hundred miles an hour, twice the speed of sound, if you are a civilian without access to the latest, fastest military aircraft. The journey that used to take three weeks under sail from London to New York City now takes us as little as two and a half hours, sipping champagne the whole way.