Final answer:
The Athenians counter the Melians' belief in the assistance of the gods with the famous dictum that, 'The strong do as they can and the weak suffer what they must.'
Step-by-step explanation:
In Thucydides's History of the Peloponnesian War, the Athenians counter the Melians' belief in the assistance of the gods with the famous dictum that, "The strong do as they can and the weak suffer what they must." This statement emphasizes the Athenians' belief in their own power and dominance, asserting that those who are powerful have the freedom to act as they please, while the weaker ones are left to face the consequences.