At the end, the two characters grab a rope and toss it over their heads and onto their shoulders. In the next camera angle, the rope is gone for both, and then in the next angle, it is back again.
There is an announcement that the Mexico/USA border will close in 2 hours, 15 minute. Over twenty minutes later an announcement informs that the border will close in 2 hours.
During the shootout at the border, Dylan is firing an automatic carbine. When it runs out of ammunition, it keeps clicking as if there was some kind of motor cocking and releasing the firing pin. This isn't how small arms work. The breach would simply lock open upon ejection of the last spent cartridge.
During the battle at the Tucker's ranch house, when Dylan has the bandanna in his mouth, his mouth is bloody in one scene, and then in the next, the blood is gone. In the next scene, he has blood in his mouth again. This happen a few times.
A neo-Nazi character lists the weapons and calibres he can hear, then describes them as "home-grown music from the heartland ... American music". The three weapons he identifies by name are a Glock, AR-15 and AK-47. Of these, only the AR-15 is actually Anerican.