"America had experienced a gradual decline in the rate of serious crimes over much of the 19th and early 20th centuries. That trend was unintentionally reversed by the efforts of the Prohibition movement. The homicide rate in large cities increased from 5.6 per 100,000 population during the first decade of the century to 8.4 during the second decade when the Harrison Narcotics Act, a wave of state alcohol prohibitions, and World War I alcohol restrictions were enacted. The homicide rate increased to 10 per 100,000 population during the 1920s, a 78 percent increase over the pre-Prohibition period.
"The Volstead Act, passed to enforce the Eighteenth Amendment, had an immediate impact on crime. According to a study of 30 major U.S. cities, the number of crimes increased 24 percent between 1920 and 1921. The study revealed that during that period more money was spent on police (11.4+ percent) and more people were arrested for violating Prohibition laws (102+ percent). But increased law enforcement efforts did not appear to reduce drinking: arrests for drunkenness and disorderly conduct increased 41 percent, and arrests of drunken drivers increased 81 percent. Among crimes with victims, thefts and burglaries increased 9 percent, while homicides and incidents of assault and battery increased 13 percent." - http://www.cato.org/pubs/pas/pa-157.html
alcoholism in America was wide spread until the temperance movement started in the 1840's.
80 years before Prohibition.
Even children drank. The temperance people reduced alcoholism.
Temperance was a voluntary movement of social pressure and public awareness - that should be our approach to other drugs as well.