Is racism basically the only reason why prohibition of cannabis lasted for so long?

Racism played a significant role in the prohibition of cannabis, but it is not the only reason why the ban lasted for so long. The reasons for the initial prohibition of marijuana and hemp in the early 20th century were shaped by a range of political, economic, and social factors, including concerns about the impact of drug use on public health, as well as prejudice and fear towards Mexican immigrants and African American communities who were associated with the use of marijuana at the time.

Additionally, once the prohibition of marijuana and hemp was established, a number of other factors contributed to its persistence, including a growing criminal underworld associated with the illicit drug trade, a shift in political priorities towards a focus on law and order, and a lack of political will to reconsider the prohibition in light of new evidence and changing attitudes towards drug use.

So while racism was a significant factor in the initial prohibition of marijuana and hemp, it is not the only reason why the ban persisted for so long. Rather, it was the result of a complex and evolving mix of political, economic, and social factors that changed over time.