On the island of Corregidor at the entrance to Manila Bay, American coastal defense came to a high point in the big gun defense theory of protecting vital areas of a homeland.  Using some of the biggest guns in the American arsenal, the defenders held off the enemy for over five months.  The end came swiftly though, flaws in the system exposed terribly.  Capitulation meant the garrison force marched on to the horrors of Japanese prison camps.  With the fall of the island fortress, the theory of coastal defense would slowly re-evolve.