On the surface the letter may seem as the senseless ramblings of a senile old woman, but perhaps it's her way of advocating for a different approach to security.
Having visible, heavily armed uniformed officers present is a deterrent to the casual, spontaneous doer of evil or highjinks, but it's also an admission that there's a problem or threat that the powers that be have failed to foil.
Perhaps moving to a less visible, yet effective security force would be more appropriate?
Guards disguised as bushes or hiding in trash cans would be there in an instant should trouble visit the hill.
The lack of visible force would lull all who visit parliament into the comfortable idea that Ottawa is so safe they don't even have security.