Every year, more and more people begin to support the legalization of marijuana. We're seeing changes all across the country, as more than half of American states now allow medical marijuana. Four states voted in November to legalize recreational use.
Here's an even more startling set of numbers: According to a Gallup poll, 60 percent of Americans now support legalizing marijuana. In 1969, only 12 percent did.
So, how has the marijuana industry come so far since the '60s? And, just as importantly, why was there so much contempt for the drug then?
Start the slideshow to see 11 moments that helped shape the way we think about marijuana.
With Prohibitionist sentiment growing (the U.S. Senate proposed the 18th Amendment in 1917), the Old Bay State became the first to outlaw marijuana. Several other states followed soon after.
Woodrow Wilson signs Harrison Narcotics Tax Act in 1915.
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Composed of three U.S. House bills, the Harrison Act prohibited the importation of opiates and restricted doctors from prescribing narcotics. The primary intent was to prevent the use of opium, morphine and heroine, but the bill affected the marijuana industry, as well.
'Reefer Madness' debuts in 1936.
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The fictional story of how marijuana influenced a group of people to kill, rape and steal, Reefer Madness was originally made by a church group as a morality tale about cannabis but was purchased by Dwain Esper, a director and producer of exploitation films.
1937 was a bad year for the marijuana industry. In August, President Franklin D. Roosevelt signed into law the Marihuana Tax Act, banning cannabis. In October, Samuel R. Caldwell become the first person arrested under the Marihuana Tax Act (which was overturned by the Supreme Court in 1969 and repealed by Congress in 1970). He served three years in prison.
LaGuardia Report released in 1944.
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An opponent of the 1937 Marijuana Tax Act, New York Mayor Fiorello LaGuardia appointed a commission to study the effects of marijuana in New York City two years later, in 1939. The report was published in 1944 and contradicted claims previously made by the federal government about the dangers of marijuana.
Boggs Act introduces minimum sentencing in 1951.
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Search for "Boggs Act" in Wikipedia and you'll be automatically directed to the page on mandatory sentencing. The law made a first-time cannabis possession offense a minimum of two to 10 years with a fine up to $20,000 (close to $200,000 today when adjusted for inflation).
Nixon declares war on drugs in 1971.
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"Public enemy number one in the United States is drug abuse," said President Richard Nixon. "In order to fight and defeat this enemy, it is necessary to wage a new, all-out offensive. I've asked the Congress to provide the legislative authority and the funds to fuel this kind of offensive." Nixon then went on to scale up federal drug control agencies and categorized marijuana as a Schedule I substance, making it one of the most restricted drugs in the country along with heroin and LSD.
Jimmy Carter wins the presidency and advocates for decriminalization of marijuana in 1977.
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In a letter to Congress, Carter wrote, "Penalties against possession of a drug should not be more damaging to an individual than the use of the drug itself; and where they are, they should be changed. Nowhere is this more clear than in the laws against possession of marijuana in private for personal use." Between 1973 and 1978, 11 states decriminalized marijuana.
Marinol approved by the FDA in 1985.
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Marinol, a prescription medicine that can relieve nausea and vomiting associated with chemotherapy as well as several other symptoms, is a synthetic or chemically made form of cannibus. It was the first marijuana product approved by the FDA, followed shortly by Cesamet.
California legalizes medical marijuana in 1996.
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Though some states had decriminalized cannabis as much as 20 years before, California was the first state to legalize medical marijuana. Much of the west coast followed California's lead, such that by 2000, Oregon, Washington, Alaska, Hawaii, Nevada, Colorado and Maine had all legalized medical uses of the drug.
Four states legalize recreational marijuana in 2016.
Jonathan Wiggs | The Boston Globe | Getty Images
Somewhat surprisingly, one of the first states to legalize recreational use via ballot initiative (along with California, Nevada and Maine) was Massachusetts -- the first state to criminalize marijuana. It's all come full circle.
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