>Slave states work. GDP goes up. What's not to like?
They work when they're sitting on a mountain of oil, or Singapore's equivalent: a shipping bottleneck. Sort-of, at some point corruption becomes intolerable, or the oil runs out (or becomes too cheap to pay for the oppression).
That said, the Singapore comparison may be a little far-fetched, they resemble the West far more than the totalitarian Middle East states.