I don't. Have you ever heard a sonic boom before? Supersonic aircraft are useless over land for that reason alone, and if the regulations regarding supersonic flight over land were lifted then the net result would be a small number of wealthy jetsetters subjecting hundreds of millions to ongoing, unpredictable, maddening explosions, akin to living in a warzone. This scenario is one of the worst plausible futures that I can imagine. Supersonic passenger jets are a dead end.