Athens' strategy was to defend their city and port fromPeleponnesian siege, and send out its navy to harass the homecities of the Peloponnesians with its superior navy. Athens couldalso use its sea power to import food, so a siege could not starveit out.Late in the 27-year war, the Persians bankrolled a strongPeloponnesian navy which defeated the Athenian navy, then besiegedthe city which could now could not import food, and so was starvedinto surrender.