Why was Medo-Persia able to defeat Babylon?
Medo-Persia defeated Babylon because its military power was already greater than Babylon's; otherwise it could never have conquered them. This empire was led by two kings, Darius and Cyrus, representing the Medes and Persians, who had to agree before any military, economic, or political move.
Les explains that the Mede and Persian Empire was the next kingdom that came on the scene and defeated Babylon. Militarily, they were already greater than Babylon, otherwise they could never have defeated them. Unlike Babylon's head of gold, which was an absolute government of one who did not have to consult with anybody, Medo-Persia had two kings, Darius and Cyrus, the Medes and Persians. Before they made any kind of military, economic, or political move, they had to agree. Les points out that it is a lot harder to get two people to agree than it is for one.