The symbolism of Blood in the movie.

Blood tends to be a major theme throughout the entire movie. From the beginning to the end, blood is constantly spilt with no respect of persons. And it's all over the simple issue of money which can be traced back to greed.
 
First, it can be seen at the drug deal site where everyone involved had been shot and killed including the last man standing. Blood is spilt all over the site showing how one man was either un-willing to give up the money or someone had been attempting to take it for himself. The story is never clear, but we know that someone had screwed up the deal.
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Next, we see how blood affects the two characters Llewelyn and Anton. At the drug deal site, Llewelyn discovers the case of $2 million dollars not far away and decides to keep it for himself rather than give it to the police. We have no idea whether or not the police would actually figure out who the money belonged to or kept it for themselves, but we do know that because of Llewelyn's greed, he took the money for himself. Eventually, this decision comes back to bite him as Anton eventually finds the hotel Llewelyn is staying at and clips him with his shotgun as Llewelyn flees down the alleyway.
Llewelyn is not the only one who is shot in this scene, Anton is shot as well. If you watch closely near the end of the clip, you can see a trail of blood where Anton had dove behind a car and then took off down an alleyway.

 Even though Anton is a hired gun, it is obvious that he has no intention whatsoever of returning the money back to its owner. He wants it for himself and the affect of his greed costs him not only this scene but in the car crash scene as well (see Anton Chigurh tab).
Greed not only affects the main characters in this movie, but also those who come in contact with them. Anton blasts away people staying in a motel room next to Llwelyn so he can get to the money. In the hotel showdown clip, Llewelyn gets picked up by a stranger, and, next thing you know, the man gets shot in the head by Anton. One of the saddest scenes in the movie is definitely when Anton and Llewelyn's wife meet. The scene portrays most effectively the fact that greed even affects those who are completely innocent.
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