Is there any meaning or symbolism in the letter Q or the number 17 ? Definetly it isn't a biblical number (3,7,12,40,etc)
EDIT : I knew that it was because Q is the highest level of clearance. I wanted to know why the letter "Q" and not P, D, M, E,X, etc.
You'd have to go back to 1977 when the DOE was created since this level security has to do with that department. I am assuming Q just used the letter because of the level of security clearance and being in close proximity to the president.