Probably because he was driven by personal experiences from growing up in segregated Atlanta.
Answer:
The Peloponnesian League was an alliance in the Peloponnesus from the 6th to the 4th centuries BC, dominated by Sparta. It is known mainly for being one of the two rivals in the Peloponnesian War (431–404 BC), against the Delian League, which was dominated by Athens.
Pericles thought that since Athens had a government where power was shared by many and Athens served as an example to the other cities it was different then it's neighbors.
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