Such a seemingly passive policy, even that late in the war, seemed revolutionary to senior Japanese Army and Navy leaders. It ran counter to the deeply ingrained warrior code, which viewed the defensive as only an unpleasant interim pending resumption of the glorious offensive in which one could destroy the enemy with sword and bayonet. Even Imperial General Headquarters grew nervous. There is some evidence of a top-level request for guidance in defending against American “storm landings” from Nazi Germany, whose sad experience in trying to defend Normandy at the water’s edge had proven disastrous. The Japanese remained unconvinced. Kuribayashi needed every bit of his top connections with the Emperor to keep from being summarily relieved for his radical proposals. His was not a complete organizational victory--the Navy insisted on building gun casemates and blockhouses along the obvious landing beaches on Iwo--but in general he prevailed. Kuribayashi demanded the assistance of the finest mining engineers and fortifications specialists in the Empire. Here again, the island favored the defender. Iwo’s volcanic sand mixed readily with cement to produce superior concrete for installations; the soft rock lent itself to rapid digging. Half the garrison lay aside their weapons to labor with pick and spade. When American heavy bombers from the Seventh Air Force commenced a daily pounding of the island in early December 1944, Kuribayashi simply moved everything--weapons, command posts, barracks, aid stations--underground. These engineering achievements were remarkable. Masked gun positions provided interlocking fields of fire, miles of tunnels linked key defensive positions, every cave featured multiple outlets and ventilation tubes. One installation inside Mount Suribachi ran seven stories deep. The Americans would rarely see a live Japanese on Iwo Jima until the bitter end. American intelligence experts, aided by documents captured in Saipan and by an almost daily flow of aerial photography (and periscope-level pictures from the submarine _Spearfish_), puzzled over the “disappearing act” of the Japanese garrison. Trained photo interpreters, using stereoscopic lenses, listed nearly 700 potential targets, but all were hardened, covered, masked. The intelligence staffs knew there was no fresh water available on the island. They could see the rainwater cisterns and they knew what the average monthly rainfall would deliver. They concluded the garrison could not possibly survive under those conditions in numbers greater than 12,000 or 13,000. But Kuribayashi’s force was twice that size. The men existed on half-rations of water for months before the battle began.