Corrected entry: The national guardsmen had to scale the side of a cliff to see who was signalling them. Napolean and Amber, who were left behind, decide to join the rescue group and without ropes find the group on the cliff. When the group leave they cannot get back down the cliff. How did Amber and Napolean climb up the cliff?
Corrected entry: Throughout the movie, the Sergeant refers to themselves as the "US National Guard". It is simply "National Guard". The National Guard does not belong to the US as a whole, but to the states. The US Army is the federal government's military force.