Habitual drug use in the United States is at least as old as the nation itself. Habit Forming traces the history of unregulated drug use and dependency before 1914, when the Harrison Narcotic Tax Act limited sales of opiates and cocaine under US law. Many Americans used opiates and other drugs medically and became addicted. Some tried Hasheesh Candy, injected morphine, or visited opium dens, but neither use nor addiction was linked to crime, due to...