Factual error: All the soldiers that have rolled up sleeves have them rolled up Marine style (with the inside of the sleeve showing) despite being US Army.
Factual error: All the soldiers are wearing black t-shirts under their uniform shirt. Air Force wears black t-shirts, Army wears brown.
Continuity mistake: Sarah is called Cross, but her name is listed as 'Bowman' in the credits.
Factual error: In one scene Sarah starts her HMMWV with a key. Military HMMWV's have push-button ignition.
Character mistake: Bud keeps calling Sarah "Ma'am." Sarah is a corporal. Corporals don't get called ma'am or sir in the US Army. Bud has been in the Army for seven months. No soldier would make this mistake after the third week of boot camp. Anytime you call an enlisted man or NCO sir, you are looking at about 20-50 push-ups or sit-ups to correct you. It's conditioned into you.
Continuity mistake: Sarah's corporal insignia are wrong. They are way too large to be Army issue.
Factual error: Sarah would not be carrying a pistol In the US military during peacetime, only officers and MP's are issued pistols. Her uniform designates no such status. While she might be armed as part of the roadblock detail she'd have an M-16 or an M4 rifle.