One big part of the story missed by Fox news is that the exact same thing happened to another Marine at the same border crossing about 10 years ago. That Marine volunteered to drive his truck from Camp Pendleton to the border to pick up some tipsy Marines. He missed the last exit, had guns in his truck, and spent weeks in prison. Former congressman Brian Bilbray got him out, minus the truck.
If we had a president worth his position, we would have an air craft carrier with support ships off the coast of Mexico now with an ultimatum: Free the Marine or face the consequences.