On the other hand, North Korea got nukes in a few years, while being two orders of magnitude smaller. If anything, I'd say people tend to underestimate how much (money, effort) a totalitarian state can invest if they think it's needed. Basically - all of it, and then some. Dictatorships can be more efficient in selected categories than democracies, and they often are - it's "in the long run" and "across the board" that they are worse. If you remove all the "checks and balances", you risk having an un-removable psychopath to be a dictator for life; but you also unlock the "full power of the state" to work on a single thing, which - in some circumstances - can give you amazing results.

Plus their economy is about 1/15th of the US's and seems to be declining.