[periphrasis]

> Achilles' flaw is that he is driven entirely by Thumos, far beyond what is appropriate.

I disagree completely. If it was beyond what was appropriate, much of the meaning of the poem simply does not work. There was a story in the tradition that the suitors of Helen, after she was betrothed to Menelaus, all swore an oath to come to the aid of Menelaus if anyone harmed the sanctity of their marriage: this story appears no where in the Iliad. Homer explicitly doesn't mention it, because his characters are at Troy to win honor and glory, actions which in bronze age warrior culture were admirable and noble. For moderns, who are not part of a bronze age warrior culture, it can be difficult to contemplate just how thoroughly Agamemnon humiliates Achilles in front of the entire army in Book I. War prizes were awarded as a measure of esteem in which a warrior was held by his peers: the greater the esteem the greater the prize. Strip a man of his prize, and you strip him of his esteem, his honor, his entire reason for being. If there was no oath by the suitors, which Homer explicitly omits, then not only does Achilles lose his honor, he loses all purpose for being at Troy: he's not bound by an oath so why even fight if the fruits of that fighting will be taken from him in the most humiliating fashion possible? So of course Achilles goes back to his tent and sulks for over a dozen books of the poem. Had Achilles submitted to the humiliation Agamemnon inflicted upon him he would have added cowardice and unmanliness to his dishonor: he would have lost all respect by his peers and the social expectation would have been to commit suicide. So by withdrawing to his tent and sulking, Achilles was doing the appropriate and praise-worthy thing within the context of his (alien to ours) culture. And that choice ultimately destroys him.

[marginalia_nu]

Which is not uncommon in tragic flaws. It may often be a fundamentally good trait, just dialed up a notch or two. It's why tragedies have such power, it's not bad things happening to good people, neither is it bad people getting what they had coming; but good (but flawed) people making mistakes and only realizing it too late.

Achilles' blind rage makes him not even consider what might happen if the greatest warrior of the Acheans sits on the sidelines, who among his friends and allies might get killed.

Even Creon in Antigone, while fairly difficult to like, does what he does with fundamentally noble intentions.