Why could the Medo-Persian Empire defeat Babylon?
The Medo-Persian Empire could defeat Babylon because militarily they were already greater than Babylon. Only a stronger military force could overcome Babylon, and the Medo-Persian coalition under Darius and Cyrus had that superior strength, enabling their conquest. This military advantage was the decisive factor in their victory.
Les teaches that the Medo-Persian Empire defeated Babylon because militarily they were already greater than Babylon; otherwise they could never have defeated them. He notes that politically, the next kingdom that defeated Babylon was the Mede and Persian Empire. Unlike Babylon's absolute dictator of one, this empire had two kings, Darius and Cyrus, the Medes and Persians, who had to agree before any military, economic, or political move. Les observes it is harder to get two people to agree than one, but their military superiority made the conquest possible.