This statement and it's conclusion is so ideologically inflamed and historically wrong I don't even know where to start
You can start by giving me three counterexamples. You might find it a little harder than you expect. Athens doesn't count because it didn't have checks and balances, BTW.
Just for your information, the Roman republic became so large not because of its political system (which makes modern Russia look like an uber-democratic human rights abuse free wonderland) but because of its better military organisation (and technology, commanders, ect). Britain was successful because of its near-monopoly on naval power for most of the 19th century. And America is so powerful because of its economic strength and size compared to European powers. (please feel free to correct me if im wrong)
You need to step back a bit and ask why all those happened. How did Roman Republican institutions become better and have higher miltech? How did the US come to be able to ethnically cleanse a pretty sadly amazingly vast number of Indians and easily displace control from Florida and Texas?
For a start, voting is the least bad way of choosing leaders. And then, freedom - even if only elite freedom like Rome's early days - gives freedom to innovate and build lots of business and have a strong economy. Checks and balances let a state survive better.
I got the idea about Rome, BTW, from a Greek Roman contemporary whom wrote a history of Rome, BTW - Polybius.
And I think you aren't giving Russia enough credit. Poor Russia! ;-)
EDIT: ...and, the Hellenistic states were all particularly governmentally weak because they had no checks and balances. Kings of Macedon had a way of being mentally outsmarted by Achaean leaders, and working more to Achaean advantage than their own. The Battle of Salamis was won by a democratically elected leader lying to get Xerxes to send his fleet into a trap.