Unfortunately when Amy Winehouse kicked the bucket, no one learned anything about the dangers of drug addiction: they could never put themselves in her place, and so they believe it couldn't happen to them or any other normal person among their friends and family -- only to a complete and total freak like her.
The next time the zeitgeist enters a wild phase, they will be among the first to recklessly experiment with hard drugs, convinced that they're beyond the reach of addiction's hand. They will only find out the hard way that their brains are more frail than they'd thought. So, when there are few reminders that normal people can get sucked into an addiction if they get started, the average person gets complacent and sets themselves up for a rude awakening, either personally or again as it might strike someone they know.
Those reminders thankfully do not have to come from first-hand experience -- believable stories from the broader culture will do as well. So let's have a look at the typical attitude toward drug use a listener of popular music would have heard during the four phases of the zeitgeist cycle, the first and second halves of falling-crime and rising-crime periods. I'm going mostly based on Wikipedia's category of drug-related songs, which looks pretty comprehensive.
During the second half of falling-crime times, roughly the early-mid-2000s through today, the mood is complacency, so songs about drugs will not find much of an audience. "Well yeah we know not to smoke crack, but gosh it's not like we would anyway, so why do we need to hear about it?" Aside from Amy Winehouse's song "Rehab", where she throws a hissy fit about being told she needs to detox, and a reference here and there in a song by Pink, drugs have mostly disappeared from pop songs. This appears to be true for the previous second half of falling-crime times, namely the later 1940s through the '50s.
In the first half of falling-crime times, boredom and nihilism set in, and drugs are permitted, even if not celebrated, as an escapist way to shock some sensation back into the corpse of your social life. From 1992 through the late '90s or early 2000s, this attitude could easily be seen in the gangsta rap trend in black culture -- such as Snoop Doggy Dogg's 1993 solo hit "Gin and Juice" -- and in the dropout heroin chic trend in white culture -- for example "Ebeneezer Goode" by The Shamen in 1992, "Cigarettes & Alcohol" by Oasis in 1994, and "Beetlebum" by Blur in 1997. The only major song that showed the destruction of getting into drugs was Green Day's 1995 "Geek Stink Breath", about meth addiction. However, as I remember it, no one knew what it was about, unless maybe they bought the album and read the lyrics.
It looks like the same attitude prevailed during the previous first half of falling-crime times, 1933 through the mid-'40s, as shown by Cab Calloway's 1933 song "Reefer Man" and Ella Fitzgerald's song "Wacky Dust" from 1938.
When violence levels start soaring, people see that the old ways have not managed to keep them safe, so they switch to a more experimental mindset in order to figure out through trial-and-error how to adapt to the dangerous new world. In the first half, there has not been enough time to sort out the proven successes from the failures among the experiments. So there is a sort of anything-goes attitude about drug use -- it's just part of the overall expansion of consciousness.
There are too many songs in this vein from the 1960s and early '70s to review, but some of the best known are "Lucy in the Sky with Diamonds" by The Beatles, "Heroin" by Velvet Underground, and "White Rabbit" by Jefferson Airplane, all from 1967. There was a major exception -- "Kicks" by Paul Revere and the Raiders, a strongly anti-drug song from 1966. It didn't help the counter-culture that it was a rockin' tune instead of some easily dismissed stuffy propaganda song. Already by 1972, a few are starting to see how high the costs can get, as detailed in "Needle and the Damage Done" by Neil Young.
Once the society moves into the second half of rising-crime times, it's clearly not a passing trouble or two that they have to deal with, and there's been enough time to evaluate which experimental changes have proven better or worse at adapting people to the new world. By now most people begin to push back against libertine drug use. The most permissive it gets is "it's complicated, and probably for the worse," as shown in some songs from the earlier part of this period, such as "Cocaine" by Eric Clapton and "Hotel California" by Eagles, both from 1977.
Throughout the 1980s, drug songs supply their audience with vivid pictures of how free drug use will destroy the user, and perhaps even their larger community if there are enough addicts around in one place.
Strange as it is to believe, rap songs about drugs back then were the most intolerant, especially when compared to the later apathetic and indulgent attitude of gangsta rap. When cocaine and crack are tearing apart your neighborhood, though, it's hard to wave them on by as fun activities for sound-minded adults to take part in. "White Lines" by Grandmaster Flash (1983) spares no detail about the short-term effects on the user's own brain, as well as the downstream consequences for being able to live an autonomous life. "Night of the Living Baseheads" by Public Enemy (1987) paints a grim picture of what life looks like when crackheads start taking over the 'hood. Even N.W.A. wrote a song like that -- "Dopeman" from 1987 -- before they took off in separate gangsta rap directions and glorified and glamorized the drug culture. As late as 1988, Ice-T was telling his audience not to touch drugs and to get hooked on his music instead ("I'm Your Pusher").
In white people music, the only popular song of this period that romanticized the drug world was "Dr. Feelgood" by Motley Crue in 1989. Although it is ostensibly a love song, "I Want a New Drug" by Huey Lewis and the News (1983) details all sorts of horrible side-effects of drug use. "Welcome to the Jungle" by Guns N' Roses (1987) half-glamorizes the street pushers by making their world seem exotic, but the overall message is clear that they're just going to chew you up and spit you out -- "I'm gonna watch you bleed," "Welcome to the jungle baby, you're gonna die."
Also on that album was "Mr. Brownstone," a don't-let-it-happen-to-you-too song about needing more and more to feel the same rush from heroin, as it takes over your life. This image of the drug as a parasite manipulating the behavior of its host was made even clearer in Metallica's 1986 song "Master of Puppets".
It shouldn't be surprising that heavy metal took such an interest in stemming the free flow of drugs, since their fans were like those of the rap genre -- lower on the class ladder, more impulsive, less socially integrated into their communities, and in general having more of a slacker / stoner / dropout / burnout tendency. Maybe the "Just Say No" campaign would work on kids who were pretty well behaved to begin with, and only needed a stern reminder from the First Lady. But the burnouts needed to be warned by their idols who had been to hell and back that it's not all it's cracked up to be.
The last two major songs in the cautionary tale genre were "True Faith" in 1987 by New Order (used in the movie versions of American Psycho and Bright Lights, Big City), and the most well known of all, "Under the Bridge" by Red Hot Chili Peppers from 1991. If the people running the D.A.R.E. program had any brains, they would have made that their theme song and played it in our fifth grade class to drive home what happens to heroin addicts.
Some crimes are the province mostly or only of people with fairly sociopathic personalities -- cold-blooded murder, rape, grand theft, and so on. Normal people aren't going to wander carelessly into this area of human behavior, so they don't need to be reminded that it's wrong. But there are all sorts of lesser crimes and vices that we need vivid reminders about, lest we grow complacent and think we can get away scot-free -- adultery, other forms of betrayal, drug use, etc.
So, there is such a thing as too low of drug use prevalence, and too little focus on it in pop culture. If it's everywhere, society is just about to fall apart. Yet we've never seen that in Western history, so that extreme seems unlikely. But if it's too absent, we forget the dangers, grow complacent, and then the next time a wild phase comes around, instead of being savvy, we wade heedlessly toward the whirlpool because, hey, we've gone strolling along the shoreline before -- what could be so harmful about that vortex out there?
Our drug policy, then, shouldn't have the goal of totally eliminating drug usage. That would look nice and stable for awhile, until the growing hubris would put everyone at risk for a real clobbering once they eventually thought about trying drugs. The same goes for popular culture -- the "family values" movement that wants to keep children and adolescents ignorant of the uglier parts of the real world is only giving them a false sense of protection. Thinking that only Amy Winehouse types could get hooked on drugs, they'll have no self-defense training for when they must confront the decision to start drugs or not, even recreationally. And they'll have the easiest time rationalizing away their indulgence, not having heard those lame and overly confident excuses a million times before.
Remember that the young people who launched the druggie liberation movement of the 1960s had grown up during the naive '40s and '50s under the watch of helicopter parents. It was those who grew up during the later half of the '70s and '80s who developed a sense of caution, whether they were doing drugs or not.