When drugs were banned they were increasingly being used everywhere. Vin Mariani [1], a wine loaded with cocaine, was not only the inspiration for CocaCola's original recipe of cocaine+kola nut, but was endorsee by countless upstanding individuals. Thomas Edison was among them - praising the drink for increasing his energy levels and helping him stay awake.
Beyond this employers were giving it to workers to increase their productivity and more - we were basically turning into a nation of coke heads.
Now long after its ban you can obviously still get it, relatively easily even, but it's relegated to the darker recesses of society, like the White House, and that is undoubtedly a tremendous improvement.
Good is not the enemy of perfect.