what, does every freakin movie now days have to have some stupid political meaning?
Because people have:
A) Subconcious thoughts
B) Assumptions about their world
No matter what they create this subconcious thoughts and assumptions creep into their creations... It doesn't matter whether or not the director means to put messages into a movie, he draws on his brain, a brain which contains his biased picture of the world. If he explores themes (Honor, Duty, Glory, Combat and Victory) then they are explored from his biased perspective, with his assumptions, correct or not, and parallels to real life, where he got those assumptions and subconcoius thoughts from, can be drawn.
Some psychologists make a living analyzing writing for the thoughts of it's writer, even though he did not mean to put them down... even if it's a completely fictional story...
To assume that there are no messages within a movie, simply because you didn't see them, or would like to enjoy the surface level of a movie, or because the director didn't mean to put them there, then you are making an ignorant assumption. I believe if you continue your education, particularly in psychology or philosphy or human behavior, you will find that you are wrong.
As for what this movie was about?
Martyrdom. Plain and simple. This movie centered around the concept of dying for the freedom of others... that's your climax. To say that that theme has relevance in today's Join-the-Army-but-we-won't-draft-you world is an understatement and "Freedom don't come free" type propaganda found it's way into the movie, no doubt. The power of a martyr turned everything around. Look at the Civil Rights movement... heck, look at Iraqi insurgents... would they fight so hard if they hadn't seen Saddam hung on international television live? Not likely. Jesus Christ. No, literally, Jesus Christ. Martyrdom is, quite possibly, the most powerful thing in the world, and it was Leonidas' plan to use it to save his people from the beginning.
And Freedom. The power to bow to no man. The movie slyly posits that for such a right, to have no master, one must die. Xerxes bows to no man, but he is not free, for he has to serve his own imaginary godhood, and thus, is not truly free... Leonidas is, but he cannot remain free and live, and so he chooses death... but then isn't death unavoidable... wouldn't he just prolong his death by waiting in the city at the orders of the council? "What must a free man do?" A free man must die... obviously... and back to martyrdom.
There are other minor themes here, you can draw parallels to any army that believes it's cause noble and it's enemy overpowering, so that includes viewing the either the Spartans OR Xerxes as Bush/America in the Iraqui war, depending upon what you want to focus on... there is some anti-religious sentiment to be had (not exactly rare nowadays, is it? I swear, no one knows what balance is anymore), with the only religion portrayed being strictly adhered to and obviously corrupt and wholly incorrect. The illusion of kindess is implied (the good guys are cruel, and the villain is kind (why did they center on that so hard?)). As the origional post posted, there is a TON of imagery here, and you don't have to 'dig deep' and come up with imaginative parallels for the spartans pushing the persians off the cliff... the messages are hit over the head of the alert pretty thoroughly...
Doesn't make it not a good movie... doesn't mean the action doesn't take center stage, but I'm not going to blind myself to something simply because it's inconvenient for some...