Scrolling through my radio dial this morning, I hit on KLIF 570AM just long enough to hear talk show host Darrell Ankarlo warn listeners about a sinister plot: the “quiet war of colonization” by Mexicans who wish to “take back America” for Mexico, or at least the (formerly) Mexican people. Oh, brother. How, you wonder, can these guys like Ankarlo serve up such fear-mongering idiocy day after day? The answer: because it works. If you want to really understand this ever more powerful medium, the best story ever done about it is available free online for a short period of time. It’s HOST: Talk Radio in America brilliantly written by David Foster Wallace for Atlantic Monthly. You’ll never listen the same way again.