Surely the Belgian government is free to decide how to enforce copyright law within Belgium? It's not like copyright is the same the world over. I'm from Canada for instance, and we have very different fair use (fair dealing) laws from the US, different copyright terms, etc.
> Surely the Belgian government is free to decide how to enforce copyright law within Belgium?
Only to the extent that it doesn't conflict with their international obligation pertaining to the subject: in the hierachy of law, international treaties generally stand above national laws.
It's a bit more complicated when it comes to the US, because internally the country has 3 different concepts corresponding to international treaties: treaties in the constitutional sense (covered by the treaty clause), congressional agreements, and executive agreements. The differences are:
* executive agreements (a treaty agreed to by the executive alone) stands below federal law, and can not contradict it (to say nothing of the constitution)
* congressional agreements are essentially regular laws, and thus restricted to the enumerated powers of Congress and the Executive
* "constitutional" treaties can expand beyond the enumerated powers
