What was the source of the political outcry for prohibitions on both? For alchohol it was widespread abuse. Wife beating, child abuse, broken families, violence -- all the fruits of too much intoxication, easy availibilty of distilled spirits.
But for las drugas, drugs -- marijuana, heroin, cocaine -- it was not such rampant abuse. There was abuse, there always is to some extent -- for example, today, prescription drugs are widely abused -- Kennedy's Ambien nightmare just a timely historic marker for that. In the early 1900's -- the age of the KKK -- what drove the Federal drug laws was racism. Fear of the marijuana toking negro or Mexican bandito.