The Prohibition era in the United States began in 1920, when the 18th Amendment to the Constitution of the United States took effect. The amendment, which made the manufacture and sale of alcohol illegal, was repealed in 1933. This chart shows the equivalent in pure alcohol of the beverages consumed by the average adult person in the United States before, during, and after the Prohibition era. Consumption statistics are based on legal sales; those during Prohibition are estimates of illegal consumption. While a popular conception of the era is one of widespread disregard for the law, estimates indicate that most people obeyed the ban and alcohol consumption was cut by more than one-half.
http://www.cato.org/pubs/pas/pa-157.html
National prohibition of alcohol (1920-33)--the "noble experiment"--was undertaken to reduce crime and corruption, solve social problems, reduce the tax burden created by prisons and poorhouses, and improve health and hygiene in America. The results of that experiment clearly indicate that it was a miserable failure on all counts. The evidence affirms sound economic theory, which predicts that prohibition of mutually beneficial exchanges is doomed to failure.
What I like about this is that it cites sound economic theory. In other words, let's take a free market approach. Prohibition causes crime and drug usage to go up. The free market approach will reduce crime, and as imporantly, drug usage.
But, there's more. This goes to the point about alcohol usage going down.
The decrease in quantity consumed needs at least four qualifications--qualifications that undermine any value that a prohibitionist might claim for reduced consumption. First, the decrease was not very significant. Warburton found that the quantity of alcohol purchased may have fallen 20 percent between the prewar years 1911-14 and 1927-30. Prohibition fell far short of eliminating the consumption of alcohol.
Second, consumption of alcohol actually rose steadily after an initial drop. Annual per capita consumption had been declining since 1910, reached an all-time low during the depression of 1921, and then began to increase in 1922. Consumption would probably have surpassed pre-Prohibition levels even if Prohibition had not been repealed in 1933. Illicit production and distribution continued to expand throughout Prohibition despite ever-increasing resources devoted to enforcement... [and] new entrepreneurs in the underground economy improve techniques and expand output, while consumers begin to realize the folly of the ban.
Third, the resources devoted to enforcement of Prohibition increased along with consumption. Heightened enforcement did not curtail consumption. The annual budget of the Bureau of Prohibition went from $4.4 million to $13.4 milion during the 1920s, while Coast Guard spending on Prohibition averaged over $13 million per year. To those amounts should be added the expenditures of state and local governments.
The fourth qualification may actually be the most important: a decrease in the quantity of alcohol consumed did not make Prohibition a success. Even if we agree that society would be better off if less alcohol were consumed, it does not follow that lessening consumption through Prohibition made society better off. We must consider the overall social consequences of Prohibition, not just reduced alcohol consumption. Prohibition had pervasive (and perverse) ef fects on every aspect of alcohol production, distribution, and consumption. Changing the rules from those of the free market to those of Prohibition broke the link that prohibitionists had assumed between consumption and social evil. The rule changes also caused unintended consequences to enter the equation.
The most notable of those consequences has been labeled the "Iron Law of Prohibition" by Richard Cowan. That law states that the more intense the law enforcement, the more potent the prohibited substance becomes. When drugs or alcoholic beverages are prohibited, they will become more potent, will have greater variability in potency, will be adulterated with unknown or dangerous substances, and will not be produced and consumed under normal market constraints. The Iron Law undermines the prohibitionist case and reduces or outweighs the benefits ascribed to a decrease in consumption.
The last point goes to my point about the bad guys controlling distribution. Also, keep in mind that I am opposed to drug usage. I just feel that prohibition never works.