…actually worked fine, Rick, so long as the Empire kept its eye on the

ball. What brought down dynasties was (a) failing, through carelessness and

inattention, to keep the barbarians on the hop, and (b) letting too many of

them — like the horrible An Lu-shan (8th century) — into the army because

your own people came to disdain military service. (“You don’t use good iron

to make nails; a good son does not become a soldier”—old Chinese saying.)