This was insightful for me: ""Congress, initially as part of the War on Drugs but later expanded to include most federal offenses, criminalized almost every financial transaction that flows from funds that are the proceeds of ‘specified unlawful activity,’" Bruce Maloy, an Atlanta-based attorney and an expert in US extradition law, told Ars by e-mail. "In simplest terms, if you possess funds from a crime and do anyth…
I could be wrong about that, but as far as I'm aware it was an innocent connection to drugs. After all, if you are impeaching civil liberties you may need a smokescreen like drugs or terrorism, but making it illegal to use illegally-gained funds is something I suspect most US citizens would be OK with immediately without the need for deception.