There isn't anything special about the Internet in this context. Lots of laws are ambiguous. That's why, in the common law system, we have courts and precedent.

You missed my point: either the standard is the law, or it's "we'll let you know when we have a problem with what you're doing".

I think he may have meant, "whose laws"? If you and your client are both in the United States, and your client only has customers in the United States, that's clear. But that's also rare.

Again, it doesn't really matter. Most countries have laws and respect the rule of law. Same principle applies, except places where the rule of law doesn't hold.