Superior strategy and tactics, and continuous ruthless use of military power to achieve the desired result - repulse of the Persian invasion.
First define the Second Persian War. The Persian War ran 499-449 BCE - it had several pheses - Ionian Revolt, Persian punitive expedition against Eretria and Athens, Persian invasion of mainland Greece, Greek counter-offensive. Which among this is supposed to be 'Second Persian War?
After - Athens converted the anti-Persian Delian League which it led against the Persian Empire into an empire of their own, and used the proceeds on itself, bankrolling its Golden Age.
Which Persian War? There were ancient Persian Wars (Persia doesn't exist anymore by the way), Iran used to be called Persia. Which Persian War concerns your question.
The US Military in the Persian Gulf is used to buttress US Support for Saudi Arabia and the Gulf Countries against Iran.
Persian, primarily spoken in Iran, is also used as a second language in several countries, particularly in Afghanistan and Tajikistan, where it is known as Dari and Tajik, respectively. Additionally, Persian is spoken by expatriate communities in countries like the United States, Canada, and various European nations. In these regions, Persian serves as a cultural and linguistic link for Iranian diaspora populations.
It converted the Delian League cities it had led against the Persian Empire into an empire of its own, and ruthlessly used its financial and military resources for its own benefit and power.
The Persian Empire was expanding toward the Greek mainland. As a pretext, it used the Athenian aid to Greek Iona to send a punitive expedition against Athens after Athens rejected a diplomatic ultimatum.
They turned the alliance of cities against the Persian Empire into an empire of their own and used the financial contributions of the cities to beautify Athens and keep half its population on the public payroll.
The first Persian expedition to mainland Greece in 490 BCE was defeated o land at Marathon. The fleet was not engaged as there was no naval force deployed against it, and evacuated the survivors of the land battle. Athens did not have a viable navy until several years later, when a rich silver strike was used to build a strong navy which provided the backbone of the combined Greek cities' navy which defeated the Persian fleet at Salamis during the second Persian invasion in 480 BCE.
A modified version of the Arabic alphabet is used for Persian. It is the 28 letters of the Arabic alphabet, plus 4 additional letters used only in Persian.
Enough of the cities temporarily put aside their usual rivalries and in-fighting to form a united front against the Persian Empire. They used superior strategy and tactics - first defeating the Persian fleet to eliminate the Persian amphibious threat to their cities, and thus allow them to unite their armies, where the superiority of their armoured soldiers over the unarmoured Persian infantry gained them land victory and turned back the Persian invasion.
Words used in Persian language: Farsi or ParsiWords used in English language: Farsi or Persian