I interpreted “In my (European) country around the 1990s and got common only 15 years ago or so.” as “humans in my country started using cannabis in the 1990s for the first time”. Bringing up the larger history of cannabis use in Europe is a valid point of discussion, as it is very likely that at some point in history it was also legal and ubiquitous.
Edit: As an aside, this whole discussion began with on the topic of prohibition in regard to alcohol, which for a lot of people that term specifically refers to a period in the United States during the 1920s-1933. I’m not sure if the colonel was referring to a different European prohibition or how the rise in ubiquity of cannabis in the 90s has to do with their initial point, if at all.
> “humans in my country started using cannabis in the 1990s for the first time”.
For my point it's irrelevant if people used cannabis thousands of years ago and then stopped.
My point is that weed had no presence in culture or social acceptance pre-1990. Weed is therefore much easier to ban than alcohol and not comparable to the difficulty of banning alcohol.
I don't know the history of weed in US, but my guess is that it's roughly similar.
Edit: As an aside, this whole discussion began with on the topic of prohibition in regard to alcohol, which for a lot of people that term specifically refers to a period in the United States during the 1920s-1933. I’m not sure if the colonel was referring to a different European prohibition or how the rise in ubiquity of cannabis in the 90s has to do with their initial point, if at all.