Judging by already legal drugs, alcohol and tobacco, the general trend in use has been downward for decades; for alcohol for over a century, except for Prohibit

Judging by already legal drugs, alcohol and tobacco, the general trend in use has been downward for decades; for alcohol for over a century, except for Prohibition which caused an upward jiggle in the general trend. Before the first World War drunkeness was a major problem, and far more widespread than it is now.