Luxembourg has a drug problem. When it comes to the use of hard drugs such as heroin, the Grand Duchy is near the top, along with Spain, Slovenia and Britain.That's surprising, because Luxembourg is a wealthy and economically flourishing country with a low unemployment rate. But the fact that a great deal of money changes hands here is part of the reason. The profit margin for dealers is greater. Because of Luxembourg's tiny size, nearly every town is near a border. That makes the country interesting as a hub for international drug trafficking. Luxembourg lies along a drug-trafficking axis that runs from the Netherlands southwards to France.