Today both the left and the right still act at times as if Ehrlich’s dystopia lurks just around the corner. Progressives remain divided over whether economic growth can truly go hand in hand with environmental protection, a major political liability when many voters say that they are struggling to achieve the standard of living they want. Many conservatives, meanwhile, view the world as a zero-sum game in which Americans must fight foreign powers and immigrants to keep our slice of a pie that isn’t growing. Both of these mindsets are children of the era that produced The Population Bomb.