No Sicilian Expedition

Can Athens keep her fleet from being destroyed then? Can that lead Athens to win the Pelloponesian War?

Prior to the Sicilian Expedition, Athens had won the Pelloponesian War. She had survived Sparta's attempts to destroy her empire and had managed to get a truce and isolate Sparta diplomatically. Going into Sicily was the biggest strategic blunder in history until Barbarossa or Nappy's invasion of Russia.
 
I agree with Dr. Strangelove. No Sicilian expedition may not completely win the war outright, but will no matter what be a huge boost for the Athenians. Diplomatically, they get out unscathed, materially they save thousands of soldiers and hundreds of ships, and they keep Alcibiades from defecting, which removes the Spartans from Decelea in the late war. In short, no Syracuse could save the Athenian situation, although whether they could have maintained hegemony over greece for to much longer is questionable.
 
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