Yes it has, it has reliably kept usage down around 2% for 100 years, instead of letting it grow steadily as is NORMAL for drug addiction in a country that has legal drugs. Here is an example.
No increase in addiction in 100 years is an astonishing level of success, but some people are so STUPID as to believe that not wiping out *ALL* usage makes it a failure.
These people are simpleminded idiots who have no conception of how REALITY works. They live in a dream world utopia of absolutes that simply don't occur in the real world.