Other mistake: When James is returning to duty in one of the last scenes of the movie, apparently he is arriving in one of two twin-rotor helicopters. As the troops disembark down the rear ramp, they walk across what looks like the shadow of the elevator of a C130 Hercules airplane.
Other mistake: In the scene where Sanborn is placing Thompson's ID tags into the box the outside states he is SGT-Thompson-Matthew when in fact he was a SSG.
Other mistake: In the opening scene when Thompson is walking down to retrieve the C4 to place on the IED there are several errors, first he is walking down the tracks then he starts looking around the area and you get his point of view at T:06:09 and he is off the tracks then back on at T:06:11. At T:07:19 as Thompson is about to pick up the trailer with the C4 you can see some tanks in the foreground which is inside the blast radius, as he gets to the IED T:08:00 there are no vehicles within 25 meters of him.
Other mistake: In this opening scene when the robot is heading down to the IED the camera picks up the robots tracks as if it had already been there yet this is supposed to be the first time the team has investigated the area.
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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