The Greeks did not underestimate the Persians in the Ionian Revolt as they realized that they would be hopelessly outnumbered by the Persians if a revolt was started. Anticipating this, Aristagoras travelled to mainland Greece to rally support for the Ionian cause, only to find the two Greek cities of Athens and Eritrea were the only cities willing to commit forces to help the Ionians. Sparta, the city with the best army in mainland Greece and therefore the city whose support would be crucial to the outcome of the revolt, failed to commit troops as it was involved in wars in the Peloponnese. The Spartans' lack of support would prove costly to the Ionians as they were deprived of having the help of the only army that could pose a serious threat to the large numbers of the Persian Army.

The Athenians provided 20 ships, which was a commitment...