The War Nerd goes on an unnecessary political rant for about half of it, but he's got a valid point with the historical stuff at the beginning. The Athenians get slammed unnecessarily(A Sparta calling Athens full of boy lovers? Hilarious!) and stuff like Salamis gets ignored.
The scene where the Athenians and Spartans call out their occupations was also weird -- we're supposed to sympathize with the guys who are all warriors because slaves do all the work in their nation, and not the plucky amateurs going to defend their country? We're not supposed to sympathize with the cripple who so badly wants to help but gets turned away because of his disfigurement?
Now, this is stuff you can't lay at Zack Snyder's feet -- he just wanted to make a faithful movie version of 300 -- but it does apply to Frank Miller and his very strange worldviews.
I don't find clear parallels with the current war(you can spin it all kinds of ways, and nothing really sticks), but I will say that the Spartans make a reprehensible group of heroes. Maybe it was the baby skulls at the beginning, I dunno...