It's the opposition between Despot and true Ruler.
C5.9.Cyrus has an idea, the nature of which we shall discover later.
C5.15.

Belshazzar's feast, _vide_ Daniel, cf.Hdt.Why plural, "the trenches"?
Is Xenophon obscure?
His obscurity is mostly this: he expects his reader intelligently to follow him.
C5.32.Jars somewhat on our feelings, perhaps, in its thirst for revenge: but cf.

the feeling against the assassins of Lord Frederick Cavendish and Mr.Burke.

[Written at the time of the Phoenix Park murders.] C5.37.Is a turning-point in the rise of the archic man (and yet hardly yet, but at C5.58 we shall come to bodyguards and eunuchs).

At this highest pinnacle of {arkhe} Cyrus desires to furnish himself as befits a king.