The idea that he's referring to policy prohibitions - not technical limitations - is even more unsettling when violations of law as egregious as Clapper's lying to Congress go so conspicuously unpunished.
The entire concept of illegality as an impediment becomes meaningless when a class that's demonstrably above the law emerges in public.
Not how I read it. Obviously the technical ability to do so exists so "cannot" can only mean "aren't supposed to" in this context. Honestly I think people would have to be grasping at straws to read it any other way. What else could it possibly mean? Of course it's technically possible that's not even open for debate is it?
The debate might be how Joe Public interprets that phrase. I'd bet that more people would think that 'cannot' means 'not possible', rather than 'not supposed to'. I think that choice of words was quite deliberate for exactly this reason.
If you're a stickler for language, then yes. The word "can(not)" refers to the ability, while the words "may (not)" or "must (not)" refer to a policy constraint rather than ability.
But in common vernacular, the word "can" is used in both cases, so it's ambiguous.
"Mom, can I play on the Xbox now?" "No, you haven't finished your homework." Obviously Junior has the ability to play, but his mom won't allow him to do so.
