I didn't want to assume based on your accent alone. [he nods, pleased.]

As for the difference ... well, it's a matter of authority. If every single agent had the green light, so to speak, it would be potentially more dangerous. Only those with the authority to make arrests are allowed to carry firearms for the defense of themselves or others. It's to mitigate any unnecessary risk. Special agents are generally dispatched to investigations which still have the potential to become violent.

[careful, Newt, he'll talk your ear off if you let him, he adores his job just as much as you do yours]