Needed: Freeway & City Noise Cancellation

They have noise-cancellation headphones.  They need the same thing throughout cities.  Noise polluters should be obliged to install appropriate technologies, as soon as they become available, sufficient to counteract the noise they generate.  The idea that you can burden your neighbors with your noise — whether you are a music lover or a factory — should be as intolerable as the proposal to burden them with any other form of pollution you might generate.  People should not have to erect walls that block everyone’s view in order to protect themselves from overwhelming noise (e.g., along freeways).