Realise that Egypt, Greece, Macedonia, Rome, Persia, and China each spanned a thousand miles or more, the most effective transportation was over water, either along rivers or across seas or oceans, that ocean travel was impossible for much the year (Roman vessels were restricted to port from November through May, this lasted until the 1300s in Europe), and the minimum time for a message to traverse a thousand miles was easily ten days, if not months.
You needed autonomous lieutenants in place who could be given general orders (much like goal-seeking AI, now that I think about it), be trusted to be only modestly corrupt, not collude with enemies or others against the centre (a frequent problem), and to truthfully report what they'd experienced, in words -- writing existed, but not photography, video, audio, etc. Testimony, that is, someone's testement or attestation of fact, was all you had, though multiple testimonies could be compared against one another.
I find it interesting that every major empirical power had some intrinsic religion, probably serving as a moral check and guidance, a role that's often underappreciated today. Also that other than a set of strictures, the religions themselves often had little in common with one another: polytheistic vs. monotheistic, theistic vs. meditative, commandments vs. ancestor worship or reverence.
It's a topic on which I'm almost wholly ignorant, but find fascinating.
I think unappreciated problem with modern communications tools is that by default, they enable and encourage micromanagement.
Yet when I had to ask for a new database server, I had to submit a written request to a committee in Sunnyvale, with graphs and other supporting documentation to demonstrate that the load of the server we already had was high enough to justify it. Then I had to join a hardware review meeting, that included maybe a dozen people. One of them being either Jerry Yang or David Filo (Yahoo founders; I've forgotten which one of them it was that did these).
The people in the meeting, even excluding whichever one of the founders, easily cost Yahoo more in salaries for the time they spent discussing my request for one lonely server than the fully loaded amortised cost of operating it for a couple of years.
It's not that I have an issue with reviews, and cost controls - on the contrary, but some degree of delegation and trusting staff with budgets would have been nice. I mean, I could have trivially cost Yahoo millions of dollars with a few keypresses if I wanted to or didn't pay attention - they trusted me with the ability to mess up their entire European payments platform with basically no oversight, yet I couldn't approve a single cent of hardware expenditure for the production platform, and neither could my manager, nor, I believe, could my managers manager, who was responsible for all of engineering across Europe.
I suspect a structure like that may have created a lot of resistance to recommendations from the Paranoids even when engineering (they seemed generally very well respected; one of my old developers is part of the Paranoids now - he'd wanted to for years) would like to accommodate them for the simple reason that getting approvals would be a massive hassle and slow things down.