Continuity mistake: James is described on the cast list as a Staff Sergeant, but he wears the rank insignia of a Sergeant First Class.
Continuity mistake: During the encounter between Sgt. James and the taxi driver, James shoot to the taxi's windshield in an attempt to make the driver go, when he's backing up you can see James following him and pointing his gun to the now unbroken windshield, when scene changes, it's broken again.
Continuity mistake: When Sgt. James discovers the 5 or 6 IED's, he pulls the cord and brings them all to the surface. A few shots later when he is disarming them all, they are back under gravel. (00:23:50)
Continuity mistake: During the sniper fight, when Sanborn gets the ammunition after it is cleaned, he loads a single bullet directly into the chamber. After it is fired, a magazine magically appears loaded into the rifle and he fires a second shot.
Continuity mistake: When James returns to the base and is ordered to open his jacket, he leaves one arm raised as he reaches inside to remove his sidearm, but in the next shot, he has both arms raised again. (01:35:55)
Continuity mistake: After the last guy in the window during the sniping scenes is killed, you can see William James' face covered with sand. In a shot seconds later the sand is gone, and later reappears.
Continuity mistake: During the sniping scenes, a fresh magazine is handed from the spotter to the firer. The magazine is filled with empty cases at first. The next scene showing a close up of the mag shows it now with live rounds.
Continuity mistake: James is searching for an IED planted in a street when a taxicab suddenly speeds through the road block, which stops in front of James. James approaches the front of the taxi with his pistol aimed at the driver, then walks around to the driver's side of the car. When the shot switches to behind James, he is back standing in front of the taxi.
Continuity mistake: When James is opening his jacket he has his hand on the bottom of the jacket. Camera changes and his hand is in the air. (01:31:50)
Continuity mistake: When Sgt. James opens his jacket, he unzips it, camera cuts and he unzips it again. (01:31:40)
Continuity mistake: The circle that is drawn on Sgt. James' chest changes between shots. (01:09:50)
Continuity mistake: During the sniper scene, the amount of dust on James' face keeps changing. (01:04:10)
Continuity mistake: At the start, the guy is putting the bomb suit on and the collar is down. Camera cuts and the collar is up. (00:04:45)
Answer: The problem for the sniper was once he'd taken his shot, he was now pretty exposed. He didn't have a lot of cover and it wouldn't have taken the Americans long to figure out where the shot came from, hence why the enemy snipers made no attempt to move.
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