Intelligence in War: The Value--And Limitations--Of What the Military Can Learn About the Enemy

by John Keegan

  Despite being seen by Nagumo’s force, and despite its very low speed, the Catalina got away. Soon after it left, other American aircraft appeared. They belonged to the land-based bomber squadrons on Midway, which Captain Simard had launched before Tomonaga’s arrival. It was their absence which had prompted Tomonaga’s warning that another attack was needed; he correctly anticipated that Midway was still an offensive base. He apparently did not conclude that the missing aircraft might be on their way to intercept the Japanese mother ships. They were. Soon after seven o’clock the carriers were attacked by six Avenger dive-bombers and four B-20 Marauder medium bombers. The Avengers, though quite fast by contemporary standards, were too few in number to swamp the defence and four were shot down by anti-aircraft fire or fighters. The Marauders, which were equipped with improvised torpedo launchers, pressed their attacks right home but scored no hits; two were destroyed. Just before eight o’clock a squadron of Marine Corps aircraft from Midway, sixteen Dauntless dive-bombers and eleven obsolete Vindicators, continued the attack: the Dauntless was a robust modern bomber, soon to win a reputation as the best carrier-borne American attack aircraft in the Pacific, but the Midway Marine pilots were unfamiliar with it, and the squadron commander did not attempt to dive-bomb. Six of his Dauntlesses were shot down, two damaged; no hits were scored. Finally, at about 8:10, Midway’s fifteen Flying Fortresses appeared overhead at 20,000 feet, dropped a concentrated pattern of heavy bombs on to the carrier group and departed, unscathed, believing they had hit several ships.

  Wrongly; none of the Midway aircraft had inflicted damage to Nagumo’s ships, though they had killed some of his sailors. They had, however, seriously shaken Nagumo’s ability to think clearly. Always impulsive rather than analytical, he now allowed events instead of reason to prompt his responses. Admittedly, he was faced by a dilemma. The point of the Midway operation was not to destroy the island’s defences, or even to capture it, but to attract the surviving American carriers into a battle. The advance to Midway was the preliminary to springing a trap. Even though there was as yet no evidence of American carriers in the vicinity, Nagumo’s duty, as fleet commander, was to keep his ships prepared to fight a carrier battle if one suddenly erupted. On the other hand, he was also supposed to cover the landing force, which the defenders of Midway, if still active, might defeat. Moreover, they might launch a fourth strike on his ships.

  In the circumstances he decided at 7:15 to “break the spot,” in American parlance: to alter the arrangements on his four carriers’ flight decks from preparation for an anti-ship strike to preparation for a repetition of the attack on Midway. That required the torpedo bombers to be re-armed with bombs, the dive-bombers to be re-armed with similar fragmentation bombs instead of armour-piercing bombs. Time-consuming work, particularly as the aircraft on deck had to be struck below to the hangars. As the work began, Tomonaga’s Midway aircraft started to land, together with the Zeros of the Combat Air Patrol, to refuel. While all this complex activity was in progress, Nagumo was given word, at 7:28, of the proximity of American surface ships after all. A seaplane catapulted from the cruiser Tone, silent until then, suddenly reported “sight what appears to be ten enemy surface ships in position bearing 10 degrees, speed over 20 knots.” Tone’s seaplane, because of catapult trouble, had left half an hour late. It was now almost at the limit of its search radius.

  The news came at the worst possible moment for Nagumo. His decks were cluttered with aircraft just landed, and strewn with refuelling hoses. Many of his strike aircraft were below in the hangars, exchanging torpedoes for bombs or one sort of bomb for another sort. Yet instead of making the firm and obvious decision to launch an anti-ship strike, Nagumo dithered. He apparently thought he could cover himself by preparing for two missions at the same time. At 7:45 he signalled the fleet, “Prepare to carry out attacks on enemy fleet units. Leave torpedoes on those attack planes which have not as yet changed to bombs.”23 Then, in a brisk afterthought, he radioed Tone’s seaplane, “Ascertain ship types and maintain contact.”

  Perhaps, Nagumo may have thought Tone’s seaplane would not have found American carriers. In any case, as if to vindicate his decision to preserve some capacity to resume the attack on Midway, it was at this point that the last attack from the island, by Dauntlesses, Vindicators and Flying Fortresses, was received. Despite its failure, it disturbed the fleet’s formation and further discomposed Nagumo’s ability to analyse the tactical situation. At 7:58 Tone’s seaplane reported that the enemy fleet had changed course from 150 to 180 degrees. Nagumo demanded, “Report ship types.” At 8:09 the seaplane answered, “Enemy is composed of five cruisers and five destroyers.” Nagumo’s anxieties seemed allayed, particularly as at 8:29 the last bomb-splashes raised by Midway’s Flying Fortresses collapsed harmlessly into the sea. Refuelling and re-arming were almost complete. The moment of danger appeared to have passed.

  Then, at 8:20, just before the Fortresses departed, Tone’s maddeningly deliberate seaplane radioed, “The enemy is accompanied by what appears to be a carrier bringing up the rear.” Nagumo had made a mistake; quite how serious the next hour and twenty minutes would reveal. Tone’s seaplane crew were not wholly to be blamed for their dilatory identification of danger. The fourth of June 1942, in the north-central Pacific, was bright and sunny but the sky was spotted by clouds. The Americans flying from Midway had found the Japanese ships they sighted appearing and disappearing with bewildering rapidity. The clouds broke up their field of vision, denying a panorama. Tone’s seaplane had had the same experience.

  The consequences of its incomplete reporting, however excused, were disastrous. In the hour and twenty-seven minutes between 7:28 and 8:55, from first sighting of the American task forces and reception of the Tone seaplane’s last ominous message, “Ten enemy torpedo planes heading towards you,” Nagumo might, by better thinking, have put his fleet into a state of defence, prepared his bombers and torpedo aircraft for an anti-ship strike and got them, with a refuelled Combat Air Patrol, off the decks. As it was, though most of his Zeros were refuelled and aloft by the time the crisis came, his other aircraft were either below decks or not yet struck below, while the decks of his four carriers were littered with fuel hoses and loose ordnance.

  Spruance, commanding Enterprise and Hornet, because he could not enjoy the luxury of indecision, had reacted with single-minded positivity to the Midway Catalina’s report of Japanese proximity received at 5:34. He had first decided to close the distance to no more than a hundred miles before launching. When he got news of Tomonaga’s attack on Midway, he decided to launch earlier, making the calculation that he might thereby catch Tomonaga’s aircraft landing or waiting to be refuelled and re-armed. It was an acute judgement. Shortly after six o’clock, and although he committed his pilots to a flight of 175 instead of 100 miles, he decided to advance his launch time from 9 a.m. to 7 a.m. Fletcher, commanding Yorktown (Task Force 17), operating north of Task Force 16, decided to hold his hand. He believed that at the Coral Sea he had launched too soon and did not intend to repeat his error.

  Spruance’s strike force comprised almost equal numbers from Enterprise and Hornet: sixty-seven Dauntless dive-bombers, twenty-nine Devastator torpedo bombers and twenty Wildcat fighters to fly escort. The earliest aloft were ordered to orbit, while they waited for a full launch, so that the carriers could deliver a concentrated blow. At 7:45, however, concerned that his leading flights might run out of fuel, Spruance ordered them to set off for the Japanese. By 8:06, all were on their way. There were six squadrons in the air, Bombing 6, Scouting 6 (bombers) and Torpedo 6 from Enterprise, Bombing 8, Scouting 8 and Torpedo 8 from Hornet, with those fighters of Fighting 6 and 8 not flying Combat Air Patrol in company.

  Flying off, in 1942, was almost a stunt performance. The pilot worked up to full revolutions, released his brakes and accelerated down the deck, pulling the joystick back as he crossed the bow; engine failure or mishandling dropped him into the sea. All TF 16 aircraft made succes
sful departures, and after formating, sixty-seven Dauntless dive-bombers, twenty-nine Devastator torpedo bombers and twenty Wildcat fighters set course for Nagumo’s calculated position.

  Circumstances were to prevent their arrival in concentration. At the outset, Spruance decided to send the first four squadrons on ahead, since orbiting wasted precious fuel. Then, as they strung out towards the target, Nagumo, warned by his scouting aircraft of their approach, altered course at 9:05 from northeast to southeast. At 9:20, when Hornet’s dive-bombers reached the indicated position, they found the sea empty. Bombing 8’s leader therefore decided that Nagumo must be heading towards Midway, turned, and led his squadron due south. The aircraft were running out of fuel, however, and fifteen were forced to land on the island; the rest returned to their own carriers but all the Wildcat fighters fell into the sea with dry tanks.

  Hornet’s torpedo bombers, led by Lieutenant-Commander John Waldron, had become separated from the dive-bombers but, arriving near the target area, spotted funnel smoke on the horizon and turned to investigate. As they approached the Japanese carriers at sea level, to make their torpedo runs, they were attacked by the combat air patrol of sixty Zeros. In a few minutes all fifteen Devastators were shot down, only one pilot surviving. No hits were scored. Torpedo 8 was shortly followed by Torpedo 6, from Enterprise, which had also lost its fifteen escorts. Manoeuvring into a favourable approach, the Devastators attracted the Zeros which had just destroyed Torpedo 8 and were massacred. Only four of fourteen survived and the squadron achieved no hits. Finally, at about ten o’clock, Yorktown’s torpedo squadron, VT 3, appeared. It, too, was attacked at sea level by the Japanese combat air patrol, lost seven out of twelve aircraft and achieved nothing.

  The destruction of the torpedo bombers was not, however, in vain. Because they descended to sea level to make their dropping runs, they thereby brought down the Japanese combat air patrol from its protective high altitude. When at 10:25, therefore, yet another wave of American aircraft approached, to bomb from 14,000 feet, Nagumo’s four carriers lay open to destruction. Their decks were crowded with aircraft waiting to be launched in a retaliatory strike, draped with fuel hoses and littered with torpedoes and bombs. Akagi was the first to be hit. Nagumo’s chief of staff, Ryunosuke Kusaka, reported “a terrific fire . . . bodies all over the place.” A bomb from a dive-bomber had hit the midships elevator, penetrated to the hangar deck and set off a torpedo store. Another fell into the aircraft park. Kusaka went on, “There was a huge hole in the flight deck, just behind the amidships elevator. The elevator itself, twisted like molten glass, was drooping into the hangar. Deck plates reeled upwards in grotesque configurations. Planes stood tail up, belching livid flames and jet-black smoke, their torpedoes began to explode, making it impossible to bring the fires under control. The entire hangar area was a blazing inferno and the flames swiftly spread to the bridge.”24

  Akagi’s fate had come about by accident, not intelligence activity. The intelligence supplied to TF 16 and TF 17 had, indeed, thus far resulted only in catastrophe. The three torpedo bomber attacks, by eighty-three aircraft, had resulted in the loss of thirty-seven, together with many of their fighter escorts, and no damage to the Japanese at all. Enterprise’s dive-bombers had been led to Nagumo’s carriers by hazard. The Japanese were not where they were expected to be; they were discovered by chance. Among Nimitz’s preparations for the encounter near Midway had been the deployment of a submarine screen. One of the submarines, Nautilus, attempting to set up an attack, had been detected by the destroyer Arashi, which lingered to drop depth charges, without effect. Working up to speed to rejoin the fleet, it created a vivid white wake. Lieutenant-Commander Clarence McClusky, leading the Dauntless dive-bombers of Enterprise, saw the white streak on the surface of the ocean, guessed and turned to follow at 9:55. At 10:20 he sighted Akagi, Soryu and Kaga steaming north-west in “a circular disposition of roughly eight miles”; Hiryu was farther ahead. Their original tight, self-supporting formation had been broken up by the torpedo bomber attacks. McCusky turned to engage, leading his dive-bombers down from 14,000 feet in a seventy-degree dive. Their terminal speed almost exceeded that of the carriers’ Zeros; but they, in any case, were flying too low, having driven off the torpedo bombers, to attain a defensive altitude.

  One after another, three of the big Japanese carriers succumbed, first Akagi, Nagumo’s flagship, then Kaga, whose parked aircraft, fuel lines, bomb stores and hangars were set alight by 500- and 1,000-pound bombs. Finally, Soryu was attacked by dive-bombers from Yorktown which, launched late, were attracted to the scene by the smoke of battle and dropped bombs that, among other damage caused, folded the midships elevator back against the bridge.

  Between 10:25 on 4 June, when Nagumo was preparing to launch his anti-carrier strike, and 10:30, when Enterprise’s Bombing Squadron 6 delivered its attack, Japan’s plan to conquer the Pacific was reduced to ruins. Three of its six big carriers had been fatally struck; the fourth was to fall to American naval power before the twenty-four hours were out. Soryu was finished off in the early morning of 5 June by torpedoes from Nautilus, the submarine whose intervention had inadvertently guided the dive-bombers of Spruance and Fletcher to Nagumo’s carriers the day before. At about the same time, Hiryu, hit by dive-bombers launched from Enterprise on the afternoon of 4 June, succumbed to fatal damage sustained in that raid.

  The Japanese defeat was not to be quite unbalanced. Yorktown, which had survived grievous damage at the Coral Sea and launched one of the decisive strikes of 4 June, was found by aircraft from the still-surviving Hiryu about noon the same day and, despite the desperate efforts of its combat air patrol, hit hard. Abandoned, then reboarded by a damage control party, she was limping towards the safety of Pearl Harbor when a Japanese submarine, one unit of a screen deployed by Yamamoto to entrap Nimitz’s fleet in his great Midway scheme, found her proceeding eastward at very low speed, on 5 June, manoeuvred to intercept and fired four torpedoes. Two hit, and after a desperate death struggle, she capsized on the morning of the 6th.

  The battle of 4 June 1942—Midway—was nevertheless instantly reckoned, exultantly by the Americans, reluctantly but no less certainly by the Japanese, a dramatic victory for the power of American arms. Beginning with all the advantages, the Imperial Japanese Navy had been reduced in a few hours, indeed minutes, of hectic conflict from dominance to subordination in the struggle for control of the Pacific. The Japanese empire’s long-laid plans, to acquire an impregnable strategic holding in the Central and South Pacific and to create a world-class fleet capable of defending it against any counteroffensive, had been reversed in a few hours of violent combat.

  Yet the question remains to what extent exactly Midway was an intelligence victory. It was hailed as such by those in the know at the time and, when the facts became public knowledge, in general opinion. OP-20-G, and its outstations on Hawaii and at Melbourne, was credited with identifying, first, Japan’s decision to switch the axis of its naval offensive from the South Seas—against Australia—to the Central Pacific, next to identifying Midway as the offensive focus, then to establishing a narrow time bracket for its launching and, finally, to constructing an accurate plot of the Japanese order of battle; on 31 May, Nimitz issued a signal, 13/1221, beginning, “Estimate Midway organisation stop striking force 4 carriers [Akagi, Kaga, Hiryu, Soryu], 2 Kirishimas [battleships] 2 Tone class cruisers 12 destroyers . . . ,” an almost exact tally of the ships under Nagumo’s command. More conventional intelligence—radar contact by Midway’s station, visual sighting of Nagumo’s fleet by one of Midway’s search aircraft—established the Japanese carrier fleet’s oceanic position and speed of advance just before its first strikes were launched. That information allowed Captain Simard on Midway to launch his bomber and torpedo strikes and Admiral Fletcher to position the two task forces for their ship-to-ship attacks.

  The exactitude of the intelligence available to Nimitz and his subordinate commanders about the Midway attack was ind
eed extraordinary: enemy objective, timing, strength, direction of approach, launch position, a tick list of “information enemy” requirements; and all the more extraordinary in that most was the product of cryptanalysis. Yet it has to be recognised that, despite the riches cryptanalysis bestowed on the Americans, the result was not preordained, the outcome hung in the balance even after Fletcher had launched his aircraft towards Nagumo’s position and that contingencies and chance were critical determinants of the victory.

  Spruance risked all by his decision to launch “a full load” from Hornet and Enterprise, every dive- and torpedo bomber he had. Despite the intelligence the crews had been given, many failed to find the target. Nagumo, so much vilified in the aftermath, made a correct and prudent decision to alter course, based on a reconnaissance sighting of the incoming aircraft, before Hornet’s dive-bombers arrived. They found empty sea at the expected point of encounter, were led away in the wrong direction to search for the Japanese, missed the battle and, in the case of their escorting fighters, missed their mother ships on their return flight. TF 16’s torpedo bombers, which had become separated from the dive-bombers on the approach, detected Nagumo only by chance, at the extreme limit of vision, and were then devastated by his combat air patrol. By that stage of the battle, Nagumo would have had every reason to believe that he was winning. The events of the next few minutes would have reinforced that belief. Enterprise’s torpedo bombers had also missed Nagumo and only spotted his ships at the extreme limit of vision. They were then overwhelmed by the combat air patrol as they made their attack.