How could war be used to strengthen athens' trade empire

The Hellenic league, formed to combat the Persians, was clearly headed by Sparta. Sparta presided at meetings and provided both land and sea commanders (King Leonidas at Thermopylae, Eurybiades at Artemisium and Salamis, Pausanias at Plataea, and King Leotychides at Mycale). After Plataea and Mycale (479), the Hellenic league dispatched the fleet once again. Under Pausanias' command, they went to Cyprus and subdued large parts of the island. They also took Byzantium, thus establishing Greek control over the entrance to the Black Sea.