Dictatorships have been exceptionally successful..
The major once would include
1) Ottoman empire
2) Mongol Empire
3) Assyrian empire
etc (just in the order i remembered). Some of them lasted 100s of years.
There have not been any true democracies ( unless you count ancient Rome ) that were successful on a long run.

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Человек, который почувствовал ветер перемен, должен построить не щит от ветра, а ветряную мельницу