I don't know what other peoples' experience was, but I grew up in the 1990's in an area that was pretty middle of the road politically. Throughout elementary school, doing drugs was portrayed as something on a par with drunk driving, and got even more attention from parent groups and school administrators. In 1991, 78% of the population thought marijuana should be illegal: http://www.people-press.org/2013/04/04/majority-now-supports.... Only last year did the opinion shift in favor of legalization, and even today a substantial minority (45%) of people think marijuana should be illegal, and probably a majority of actual voters, who skew older and more conservative, feel that way.
Obviously police unions and the like will raise barriers to legalization. But let's not shirk the blame here: we created the drug war, or depending on your age, our parents did.