Continuity mistake: In one scene, some of Saddam's troops pour oil all over Mark Whalberg's face (while forcing him to bite down on a CD so it runs into his mouth) in an attempt to torture him. The next scene, when he is rescued, he has nothing but the requisite smudges and "movie dirt" on his face. Apparently the Iraqis decided to clean the oil slick off of his face before he got rescued.
Factual error: Near Karbala, during the first choppy, slow motion shootout, Mark Wahlberg is shot in the vest with an AK-47 and somehow manages to walk it off. This is preposterous. The vest issued to troops in Desert Storm (and the one he is wearing) is the PASGT fragmentation vest, which is only rated to stop shrapnel from explosions and won't even defeat a pistol round without offering severe ballistic trauma to the wearer. If you were hit with an AK-47 in a vest of that rating, it would tear through the kevlar like a hot knife through butter.
Factual error: Many people through the film are speaking Arabic and they are mostly Iraqi, but they are speaking dialects similar to Syrians & Lebanese.
Factual error: The Iraqi gunship helicopter attacking the group at the castle is an MD 500 Defender. However, Iraq has never owned or operated these helicopters.
Continuity mistake: When George Clooney is pointing his pistol at a guard in the bunker, the hammer is already cocked back (single action), but in the next shot, the hammer is down (double action) and he cocks it again.
Factual error: When Gates, Barlow, Elgin, and Vig are leaving the village after the milk truck explosion, they give the people MREs. However, the MREs they are passing out are 1996 designed packages. From 1981 until 1995, MREs had a dark brown bag while ones produced from 1996 and current are tan.
Factual error: The movie is supposed to be set in central and southern Iraq. At one point, the men are driving along in a Humvee north of Nasiriyah towards Karbala, just south west of Baghdad. Throughout this section of the film, mountains can be seen on the horizon. The actual desert of Iraq is so flat it might as well be a parking lot. The only actual geographic features of the terrain are agricultural berms, which those mountains aren't.