When Bob, Christian, and the biker are hoisting the cross up the side of the building with a rope, it somehow becomes attached to its mount on the side of the building without anyone attaching it there.
The US Army Special Forces are seen with M16 rifles. By the onset of the Global War On Terror, these had already been phased out in favor of the M4 carbine, not just in special operations, but also in most US Army light infantry units, as well.
Bob claims when the Pilgrims came to the New World 400 years ago, one of the first things they did was erect a cross on the shore of the Atlantic. Besides there being no historical record of this occurring, Pilgrims were Calvinists, meaning they aren't into cross worshiping, a major factor in them leaving England.