> But if a Brit comes to your country and buys cocaine from you, in person, you wouldn't expect to be convicted as a dealer in the UK.
No? All countries catch drug dealers from other countries all the time even for the crime that happened outside of their borders. Or do you really think El Chapo could vacation freely in Europe.
El Chapo was extradited and convicted for crimes actively committed in Mexico, then the US in relation to managing a multinational drug cartel. Murder, money laundering, more murder, smuggling, yet more murder, etc etc etc.
This seems significantly different to openly and honestly posting narcotics.