A Time of Change
The rigid, straight-laced culture of the 1950's was supplanted in the late 1960's and early 1970's by a group of young people known as hippies. The hippies questioned the values of our society with unprecendented boldness. For example, while society collectively believed that war was glorious and righteous, hippies saw it as ugly, disgusting, and terrible.
The hippies changed our world for the better. Their rebellion against the established culture of the time brought about a very different view on war; and most Americans today share the views that the hippies held. At the time they were controversial and unpopular; today they are accepted parts of our society. The hippies also explored non-Western religions and spirituality, championed protection of the environment and a return to more natural living, and preached respect and understanding for others. At the time, these concepts were neoteric to the point of being incomprehensible to the older, more conservative generation. Today, all of these concepts became ingrained in our culture and are now part of our collective belief system.
What About the Drugs?
Drugs were undoubtedly a large part of hippie culture. From marijuana to LSD to MDA, hippies explored psychedelic drug use en masse on a scale never before seen in our society. (This happened in parallel with many more formal studies, and some of those researchers blame hippies' casual drug use for the outlawing of many promising chemicals.) It drew them together and gave them an alternate perspective, allowing them to throw off the shackles of conventional thinking.
To many, however, it served as a demonstration of the potential "decay" of modern society, a decay that would accompany wide-spread drug use. This scared conventional thinkers, who were accustomed to a rigid society with little space for alternative thought or actions. Those people held the power, and they put their effort into outlawing the hippies' drugs.