There are several social, economic and political reasons why marijuana was declared illegal, and remains so today, while alcohol and tobacco (which are both far more deadly and destructive than any of the illegal drugs) are legal.

Social

Marijuana was first introduced to the United States by job-seeking immigrants from Mexico early in the 1900s. There was tremendous reactionary racism (as there is today) among white Americans toward immigrants, Mexican or otherwise. Mexicans in the Southwest were often demonized as being "lazy", "violent" and generally "no good". Marijuana use was common in the Mexican immigrant community (as was the use of opium by Chinese immigrants in the previous century), and as such it became associated with "dirty Mexicans" and their supposedly unacceptable, anti-social behavior. Subsequently, many local and state laws were passed prohibiting the possession and use of marijuana.

In later years, marijuana use became associated with black people, "beatniks", "hippies" and other folks considered undesirable by the "square" (i.e. white conservative) population. For those in love with the power structure and the status quo, marijuana became and remains a symbol of counterculture, the lower classes and non-whites.

Economic

Marijuana was first legislated against on the Federal level by the Marihuana (sic) Tax Act of 1937.
Hemp (the marijuana plant) was, in the 1930s, becoming a much cheaper and more efficient source of cellulose than wood pulp. There was a tremendous potential market for hemp as an industrial product; cellulose for paper manufacture and other products. Unfortunately for the hemp growers (and, subsequently, the marijuana users) the producers of wood pulp cellulose had no intention of seeing their lucrative market share undercut.

E.I. Du Pont De Nemours & Company, today known as Du Pont, was the nation's largest supplier of wood pulp cellulose. Du Pont contracted two banks to handle its finances, one of which was the Mellon Bank of Pittsburgh. Andrew Mellon, the bank's owner, happened to be Secretary of the Treasury. Mellon's financial interests were clearly tied to Du Pont, and he just happened to appoint Harry J. Anslinger, soon to be his nephew-in-law, to head the recently formed Federal Bureau of Narcotics.

The Federal Bureau of Narcotics began a massive anti-hemp lobbying campaign, citing all sorts of spurious "scientific" data about the dangers of hemp to the American people. This was, of course, true...if you define the "American people" as the E.I. Du Pont Nemours & Company board and shareholders.

Long story made a tad shorter, the lobbying was successful and the Marihuana (sic) Tax Act of 1937 was passed. This act was referred to in Du Pont's 1937 annual report with the languageradical changes from the revenue raising power of government would be converted into instruments for forcing acceptance of sudden new ideas of industrial and social reorganization.

Political

Largely an extension of the Social category from above. Prohibition of drugs allows politicians to do many things for themselves and others. They can appear to be "hard on crime". They can appear to care about the "public welfare". They can subsidize the prison-industrial complex and its many corporate profit mongers. They can give the defense industry a shot in the arm with more Drug War military spending. They can intervene overseas to wipe out "dangerous drugs", thereby reinforcing American hegemony. The list is nearly inexhaustible.

Imagine: a foreign country comes into the american South and wages chemical warfare to wipe out an incredibly lethal drug which the U.S. forces upon them. Tobacco. There would be outrage. Possible out and out war. Of course, when we do this in South America to subsistance coca farmers, it's okay.

Alcohol and tobacco are home grown or, at least, they feel that way. Nice, respectable, white Europeans were drinking alcohol long before they conquered the Americas. Tobacco was, of course, discovered here. It also became a lucrative trade commodity among nice, respectable, white Europeans...particularly the monarchs. All reasons to have never made these substances illegal in the first place (Prohibition notwithstanding).


Some of the above information was taken from Unraveling an American Dilemma: the Demonization of Marihuana(sic), a master's thesis written in 1995 for the Division of Humanities at Pepperdine University by John Craig Lupien. Many thanks to Mr. Lupien.