Ancient History lesson for the day:
It is rumored that they found many gold and copper metal rings called ‘deben’ at the Pharonic army headquarters site. These ‘deben rings’ of ancient Egypt were supposedly used for trade like money.
That’s why the Pentagon sections are called ‘rings’ as in A-ring, B-ring to E-ring, etc. with the high class denizens of the E-Ring being able to ingeniously demonstrate a military procurement need and then authorize the most money for defense contracts.
‘Deben,’ of course, is where the word debenture comes from.
Hmm... interesting!