Making it illegal for businesses to transact in a cryptocurrency may be technologically impossible, but most transaction volume in a country is likely to be acc

Making it illegal for businesses to transact in a cryptocurrency may be technologically impossible, but most transaction volume in a country is likely to be accounted for by large institutions and the government itself, which are going to follow the law even if technical controls forcing them to are impossible to implement. I mean, mostly. Obviously, plenty of large banks still launder money even though it's illegal. The practical end goal of any legal ban is to make the banned activity occur less than it would otherwise even if can't be stopped completely.