Not if he's been told by everyone from his immediate superior right on up to the President to stop EVERYONE!!! with an Iranian stamp.

"Please step over here, sir, while I contact my supervisor" is about what I'd expect at worst from a junior agent in this situation.

I kind of agree. I don't know how the process works which is why I'm asking for someone more knowledgeable. But my current understanding is that is how it is done.

So you mean that terrorists just need to create officially looking Norwegian diplomatic passports?

Or pretend to have lost their passport and get a new passport without stamp. Or get a secondary passport that's made available by most governments because of issues like this one.

But you are right in principle. Letting people through because they look important is a big security hole.

There's not a whole lot that border control can do to stop people who are good at making fake passports though.