The New America Foundation explains spectrum policy--graphically!: A researcher at the foundation, which describes itself as an independent, non-partisan, non-profit public policy institute, alerted me to their new (and free) report, The Citizen's Guide to the Airwaves. This handsomely and expertly produced set of writings and graphics clearly shows the disproportionate value assigned to segments of spectrum, and the lumpiness and irregular approach taken by regulatory, legislative, and executive approaches to spectrum management.
The U.S. has a crisis in spectrum because of how it's been distributed, sold, given away, allowed to be used on an unlicensed basis. This document goes a long way towards explaining the fix we're in and presents ideas about how to solve it. Even better, it quantifies so much: current value of various chunks of the frequency dial, and the potential value that could be realized.