In 1969, 84 percent of Americans surveyed by Gallup poll said that marijuana should not be legal. By 2011, 50 years later, a majority of Americans now favored legalizing marijuana, including 70 percent of Americans surveyed who "favored making it legal for doctors to prescribe marijuana in order to reduce pain and suffering," according to Gallup.

Voters approved two ballot initiatives in Colorado and Washington for the legalization of marijuana, representing the two states which have already taken the first step in order to directly challenge the drug's more than 40-year federal ban. With California first allowing the sale of medical marijuana to chronically ill patients in the '90s and Colorado and Washington fully legalizing the drug, legalization advocates have a right to think that marijuana prohibition may go the same way as alcohol prohibition did.

Marijuana gained popularity in the United States as an intoxicant in the 1920s and 1930s, when violent crimes allegedly committed by immigrants intoxicated by marijuana became publicized by tabloid newspapers and the Federal Bureau of Narcotics, in order to get Congress to approve the Marihuana Tax Act of 1937, illegalizing the substance.

President Richard Nixon signed into law the Controlled Substances Act in 1970, establishing the drug schedules system and designated marijuana as a Schedule I narcotic. The anti-marijuana movement was based on a moralizing argument that marijuana was "a deadly, addictive drug that enslaved its users and turned them into violent, deranged freaks," according to the Daily Beast's Martin E. Lee.

When America tried alcohol prohibition between 1919 and 1931, the country and its lawmakers discovered that the crime and violence associated with prohibition law ended up being more damaging than consumption of the drug itself. If the tobacco industry has taught America anything, it is that education and further regulation is the most effective way to discourage its use.

The 18th Amendment to prohibit alcohol was passed by Congress in 1917 and ratified by the states, going into effect on Jan. 17, 1920. Alcohol prohibition became a law due to the political power of the Temperance Movement of the early 19th century which saw alcohol as a "great evil to be eradicated -- if America were ever to be fully cleansed of sin," according to PBS.org.

"As argued by Harvard's Mark Moore and other astute policy observers, alcohol prohibition had beneficial effects along with the negative ones. Alcohol use plummeted among the general population. Thousands of government bureaucrats and law enforcers were employed. Cirrhosis of the liver fell by 66 percent among men. A whole industry of 1,300 breweries was ended. Arrests for public drunkenness declined by half. Federal alcohol tax revenues dropped from $482 million to $13 million," according to Smart Approaches.

On the other hand, "organized crime was emboldened and the alcohol traffickers occasionally shot up a neighborhood, but there were also twice as many speakeasies during Prohibition than saloons before it, and they increasingly sold more potent whiskey instead of beer and wine." The 18th Amendment was irregularly enforced and was sometimes practically ignored altogether.

Prohibition of marijuana creates a similar black market leading to drug trades and violence, similar to what happened during the prohibition era. Marijuana drug enforcement has been a centerpiece of the ongoing war on drugs and after the states voted to legalize the drug, the DEA issued the following statement:

"The Department's enforcement of the Controlled Substances Act remains unchanged. In enacting the Controlled Substances Act, Congress determined that marijuana is a Schedule I controlled substance. We are reviewing the ballot initiatives and have no additional comment at this time." This means that even with the legalization of marijuana in two states, on the federal level authorities have reaffirmed that marijuana remains an illicit substance for which violators can be prosecuted no matter what state they live in.

Gangs make considerable amounts of money selling marijuana; Mexican drug cartels make more than 60 percent of their profits from marijuana alone and control distribution networks in more than 250 American cities. Keeping marijuana illegal and confined to the black market creates a virtual monopoly on the lucrative marijuana trade, in what some estimate to be America's largest cash crop, a $36 billion-a-year industry larger than corn and wheat combined.

Today, marijuana is the third most popular recreational drug of choice in the United States with nearly 70 million Americans having smoked marijuana at some point in their lives, including 18 million who have smoked marijuana within the last year and ten million who are regular marijuana smokers, the majority of whom individuals are law-abiding citizens who work hard, raise families, and contribute to their communities, that is, they are not part of the crime problem at all.

The Clinton administration waged the most intensive war on marijuana smokers compared to any other presidency in history. Law enforcement today arrests a marijuana smoker every 45 seconds in America posing a tremendous cost to society; creating a 60 percent increase in marijuana arrests since Clinton took office with over ten million Americans have been arrested on marijuana charges since 1972.

Harsh federal and state penalties mean that marijuana offenders may be sentenced to lengthy jail terms and an array of additional punishments such as loss of driver's license, loss of occupational license, loss of child custody, loss of federal benefits, and removal from public housing. Suspected marijuana offenders lose their cars, cash, boats, land, business equipment and houses, although 80 percent of the individuals whose assets are seized are never charged with a crime.

The economic pros and cons of legalization are not hard to quantify: Legal businesses lead to more jobs and economic growth but also require police officers to enforce the regulations. Alcohol is the cause of 1 million more arrests annually than all other illegal drugs combined and leads to $180 billion in costs associated with healthcare, the criminal justice system and lost productivity.

Nonviolent marijuana offenders often receive longer prison sentences than violent offenders, at a cost of $23,000 per year, meaning that marijuana prohibition costs taxpayers at least $7.5 billion annually, an amount of federal dollars which can be used to combat violent crime, improve the economy or education system.

Perhaps worst of all, marijuana prohibition disproportionately impacts minorities. Blacks and Hispanics are over-represented both in the numbers of arrests and in the numbers of incarcerated marijuana offenders. Blacks and Hispanics comprise 58 percent of the marijuana offenders sentenced under federal law despite making up just 20 percent of the marijuana smokers in the United States.

Marijuana prohibition seems to be following more or less the same path to repeal as alcohol prohibition. According to deputy director of the National Organization for the Reform of Marijuana Laws, Paul Armentano: "Alcohol prohibition fell when a sufficient number of states enacted legislation repealing the state's alcohol prohibition laws." State legislatures' decisions to repeal alcohol prohibition led to the 18th Amendment to be repealed by Congress.

In his 1932 campaign, Franklin D. Roosevelt included the repeal of Prohibition in the Democratic party platform and later the law was finally repealed at the national level through an act of Congress with the passage of the 21st Amendment. At this point, neither party in American politics has given any indication of adopting a similar stance in regarding the repeal of cannabis prohibition.