During a state of war between the United States and another nation, or when hostile action by a foreign power appears imminent, the head of an agency of the United States Government may authorize the destruction of records in his legal custody situated in a military or naval establishment, ship, or other depository outside the territorial limits of continental United States—
((1)) the retention of which would be prejudicial to the interests of the United States or
((2)) which occupy space urgently needed for military purposes and are, in his opinion, without sufficient administrative, legal, research, or other value to warrant their continued preservation.