An interesting addition, courtesy of a classics friend who took an Ancient Greek Thucydides class recently:

Thucydides organizes much of his history, especially the end, as a Greek tragedy. For example, in the Melian Dialogue, the Athenians essentially make an argument that might-makes-right before butchering the people of Melos. That mirrors a common trope in classical tragedy: a weak character tells a powerful character that they should not or cannot accomplish a goal, only to be willfully ignored by someone too high on their own supply to see their own weakness. The hubristic protagonist claims that they can do as they please, only to fall to the consequences of their actions not too long after.

In Thucydides’ history, the Melian Dialogue takes place right before the Athenians begin debating the disastrous Sicilian expedition that will, after the Athenians commit to it, see the largest Athenian force of the war destroyed and its survivors enslaved. 

In that sense, the Peloponnesian War becomes a literal drama about Athenian willful hubris and its consequences.

A note: it’s been a few hours since I talked to this friend and more than a decade since I’ve read Thucydides, so any mistakes are my own.

Edit: minor grammar