by Ian W. Toll
The ploy had succeeded brilliantly, providing outright confirmation that “AF” was indeed Midway. But OP-20-G, incredibly, did not relent. Perhaps, they suggested, the Japanese were trying to mislead the Allies with radio deception? Or, as a fallback, perhaps the Japanese were planning an operation against Midway, but it would not take place until the second half of June, after another major offensive in the South Pacific?
Nimitz was under intense strain. Admiral Halsey’s Task Force 16, built around the Enterprise and Hornet, had been sent south across the equator to provide support to their sisters Lexington and Yorktown in the Battle of the Coral Sea. They had reached the waters east of Efate, in the New Hebrides. If Rochefort and Layton were right, and the Japanese were planning a huge offensive against Midway in the first week of June, Nimitz needed to summon Halsey back from the South Pacific right away. But he did not have an entirely free hand to recall the carriers, because Admiral King, who was not yet convinced of the Midway theory, was looking over his shoulder. How directly could the CINCPAC afford to defy the autocratic COMINCH?
On May 16, Nimitz threw down the gauntlet. He radioed Halsey: “Desire you proceed to Hawaiian area.” He laid out his reasons in a cable to King the same day. The Japanese would mount an attack “against Midway-Oahu line, probably involving initially a major landing attack against Midway, for which it is believed the enemy’s main striking force will be employed.” Further, the CINCPAC diary noted: “Unless the enemy is using radio deception on a grand scale, we have a fairly good idea of his intentions.”
The order prompted Admiral King to call his advisers into his office for a thorough evaluation of the latest intelligence. By the end of the day, he concluded that Nimitz was right. In an “urgent and confidential” cable the next morning, he wrote: “I have somewhat revised my estimate and now generally agree with you.” The new offensive would be aimed at capturing Midway, and in the course of the campaign, the Japanese navy would attempt to “trap and destroy a substantial portion of the Pacific Fleet.” King agreed that the American carriers should be positioned to give battle, but added that Nimitz must “not repeat not allow our forces to accept such decisive action as would be likely to incur heavy losses.”
Even now, however, critical details were missing. When would the attack come? What forces would be involved? What was the exact sequence of attacks? On May 18, Nimitz turned up pressure on Layton and Rochefort to provide answers. Communications intelligence was now more important to the Americans than it had ever been before: at that moment, the entire fleet was being staked on a series of intercepts and a complex matrix of deductions.
On May 20, Hypo received a long radio intercept—its length gave away its importance—and the cryptanalysts turned their full attention to breaking it. The IBM tabulators stripped the additives and converted more than 80 percent of the transmission to plaintext. It provided complete orders for the Midway operation, including a detailed description of the forces to be employed. But the super-enciphered poly-alphabetic time-date codes in the message remained impenetrable, so the Hawaiians could not yet prove that the attack would come the first week of June. Rochefort and Layton closed in on the date gradually, marshalling the evidence point by point. Stray decrypts referred to a May 27 sailing date from Saipan, and a June 6 arrival date for a division of destroyers that were to protect invasion transports. Layton recalled that he had worked “by applying the rule that when you don’t know things, you had to try to see them as if you were a Jap. Working backward from the sailing dates, and the decrypted orders for the 6 June arrival of the invasion force transports, I reconstructed a tentative plot that was accurate enough to predict when and where the transports carrying the assault troops should be sighted by search planes from Midway.”
On the morning of May 27, Rochefort and Layton met with Nimitz and several senior members of his staff in a conference room at the fleet headquarters. Rear Admiral Raymond Ames Spruance, soon to be appointed commander of Task Force 16, was present, as was General Emmons, the local army commander, and Lieutenant General Robert C. Richardson, who had been sent to Hawaii as a personal emissary of General Marshall. Rochefort, who was pulling together briefing materials at the last minute, turned up half an hour late. (He was perhaps the only naval officer in the Pacific who could get away with that.) Layton recalled that Rochefort appeared “disheveled and bleary-eyed from lack of sleep,” and that his apology was met by Nimitz’s “icy gaze.”
Rochefort’s forecasts—a carrier air attack on Dutch Harbor at dawn on June 3, followed by another on Midway the next morning—were so specific that several members of Nimitz’s staff found them difficult to believe. Was it really possible that the Americans were reading the enemy’s entire playbook? Some continued to suspect that the Japanese had cooked up an elaborate ruse: an entry in the CINCPAC diary that day reads: “Of course it may turn out that the Japanese are pulling our leg and using radio deception on a grand scale.” Others asked why the Japanese would hurl their entire fleet against Midway, when the atoll’s capture made so little strategic sense. (Their objections were essentially the same as those put to Yamamoto by Admiral Kondo and the Japanese Naval General Staff.) Rochefort was surprised at the degree of skepticism—to his mind, the case was, if not exactly airtight, at least proven beyond a reasonable doubt. “Of course,” he later said, “as somebody who had been living this development over two months to the exclusion of everything else. . . . I just could not understand why there should be any doubt in anyone’s mind.”
As Nimitz probed for flaws in Rochefort’s reasoning, the latter freely admitted that there were gaps in his knowledge, and that those gaps had been filled with inferences and deductions. “All I can do in a situation like this is to explain my position and hope that the admiral accepts it,” Rochefort said. Nimitz alone bore the “horrible” burden of command: “It stops right there, and no one else can take it away from him, and no one else can help him.”
The admiral turned to Layton and asked him to predict exactly how he believed the coming battle would unfold.
“I have a difficult time being specific,” replied Layton.
Nimitz held his gaze. “I want you to be specific,” he said. “After all, this is the job I have given you—to be the admiral commanding the Japanese forces, and tell me what is going on.”
“All right then, Admiral,” Layton said. “I’ve previously given you the intelligence that the carriers will probably attack Midway on the morning of the 4th of June, so we’ll pick the 4th of June for the day. They’ll come in from the northwest on bearing 325 degrees and they will be sighted at about 175 miles from Midway, and the time will be about 0600 Midway time.”
That afternoon, Nimitz issued Operation Plan 29-42, which stated that the Japanese would “attempt the capture of Midway in the near future.” The Enterprise-Hornet Task Force (16) would proceed to the suitably code-named Point luck, about 350 miles northeast of Midway. There they would rendezvous with Admiral Fletcher and Task Force 17, comprising the newly repaired Yorktown and her eight screening vessels. The three American flattops would lie in wait until the Japanese carriers were spotted by air reconnaissance, and then launch a surprise attack on Nagumo’s flank. The commanders were to “inflict maximum damage on enemy by employing strong attrition tactics,” but they should not “accept such decisive action as would be likely to incur heavy losses in our carriers and cruisers.”
Nimitz, wrote Layton, had “crossed his Rubicon.” The entire war now hung in the balance, and Layton could not sleep at all that night.
The Hypo staff was aware that the entire war had been staked on their forecast. The week before the Battle of Midway was a breathless interlude. Had they got it right? Rochefort urged his colleagues not to worry. The die was cast—the Japanese fleet had presumably sailed, and Nimitz had moved his forces into position. Even if the attack did not come on June 3 or 4, it would come in mid-June without fail. “If we get ready for this attack on June 3 and it does not come o
ff, we may look silly, but there will be time for our ships to refuel and get back on station,” Rochefort told Layton. “If we are not prepared and the Japs strike, it will be a case of Pearl Harbor all over again—and the navy will have no excuse.”
But Hypo had one more crowning victory to add to its record. The Japanese had used a super-enciphered time-date code in many of its communications, including Yamamoto’s long battle plan, which had been sent out to the fleet on May 20. Rochefort’s unit had been so engrossed in breaking new messages that it had not found the time to focus on the problem. On the night of May 26, Ham Wright had just completed a twelve-hour shift and was about to walk out the door when Lieutenant Joseph Finnegan accosted him and said, “Ham, we’re stuck on the date and time.” Wright went back to his desk, cleared off the clutter, and concentrated on the problem. He collected and collated every message intercept in which the code had appeared. He began working through the possibilities, linking old codes to dates that were known after the operations in question had been completed. One by one, with painstaking care, he constructed hypotheses, tested them, and discarded them. Later that night, Wright and Finnegan drew the dungeon’s other veteran cryptanalysts into the effort, including Tom Dyer and Rochefort himself.
By mid-morning on the 27th, they had it. The time-date cipher was a simple substitution code, using a table of kana twelve rows down (months) and thirty-one columns across (days). It confirmed that the Japanese attacks on the Aleutians would commence on June 3, and the attack on Midway a day later. It was exactly as Hypo had forecast, and exactly as Nimitz had spelled it out in his orders to the fleet.
With this victory in hand, Jasper Holmes went upstairs to absorb some sunshine and breathe some fresh air. While standing on the Administration Building’s lanai, he ran into an old friend, an officer now serving on the Yorktown. As they chatted, Dyer emerged from the dungeon, on his way home, with his battered lunchbox under his arm. He had been working around the clock for several days. Holmes wrote:
His uniform looked as though he had slept in it for three days. He had. He was unshaven and his hair looked as though it had not been cut for a month. It had not. His eyes were bloodshot from lack of sleep, and his gait betrayed how close he was to utter exhaustion. With a seaman’s contempt for a landlubber, my carrier friend remarked, “Now there goes a bird who should be sent to sea to get straightened out.” For an instant my blood pressure soared to the bursting point and I nearly blurted out the truth. Dyer was one of the kingpins of the little band of officers whose genius and devotion to duty, over many years, had given us an opportunity to win a victory at last. If he wasted his time on spit, polish, and punctilio, the war would be much longer and cost many more lives. Fortunately, I regained control of myself in time and mumbled something like, “Oh, he’s all right,” feeling like Peter when he betrayed the Lord. Dyer would have been the first to condemn me if I had broken the secrecy that we all prized much more than any credit or the hope of reward.
ADMIRAL HALSEY’S TASK FORCE 16 had arrived in the South Seas too late for the Battle of the Coral Sea. The radio operators of the two carriers (Enterprise and Hornet) had followed the progress of the battle by eavesdropping at long distance on the transmissions of Fletcher’s ships and pilots. News of the Lexington’s loss came as a cruel shock. She was the first American carrier ever destroyed in naval combat. Alvin Kernan wrote that many of the Enterprise’s veteran carrier sailors had served on the Lexington in the past—to them, in particular, her sinking “was felt as a personal blow.”
The officers and men craved revenge, and at first there was some hope of hunting down the Japanese naval forces as they withdrew from the Coral Sea. Having delivered a marine fighter squadron to Efate on May 11, Task Force 16 was free to engage the enemy, who was believed to be aiming a new attack against islands east of the Solomons. The carriers cruised north along the 170th meridian and conducted long-range searches to the west, with some hope of pinning down the retreating Japanese forces.
Nimitz’s May 16 recall order had included an unusual proviso. In an “eyes-only” message to Halsey, the CINCPAC had instructed that the task force should allow itself to be sighted by a Japanese patrol plane before turning north for Pearl Harbor. That bit of subterfuge was intended to lull the Japanese into believing that the road to Midway was clear, and to deter any further near-term aggression in the South Pacific. Halsey pointed the task force west, knowing full well that the heading would take them under the search umbrella of the ubiquitous Kawanishis. A Tulagi-based long-range patrol spotted the task force several hundred miles east of the Solomons Islands, prompting Admiral Inouye to rule out any renewed effort against Moresby before July. Then Halsey turned north and began a high-speed run toward Oahu.
Only Halsey and a few other senior officers knew what was up. Down the ranks, these quixotic maneuvers were interpreted with a combination of bafflement and disgust. Robert Casey, aboard the Salt Lake City, thought it strange that the force had been sighted, when it could easily have concealed its presence by hanging back to the east, and noted: “There’s something fishy about this.” With the task force racing north at 20 knots, it was obvious that they were hurrying home to Pearl Harbor, and it felt uncomfortably like a retreat. “It seemed to us like craven cowardice,” Kernan recalled; “. . . and there was a good deal of muttering.”
On May 26, under a sweltering tropical sun, the twenty-one ships of Task Force 16 crawled into Pearl Harbor. Though the Yorktown and her screening vessels had not yet even arrived, the East Loch was crammed full of ships, and maneuvering among them was difficult, delicate work. Minutes after the Enterprise was safely in her berth, Halsey and his flag lieutenant descended into the admiral’s barge to be taken across to the Pacific Fleet headquarters.
When Nimitz and Halsey came face to face, the CINCPAC was taken aback. The task force commander was not well. He was gaunt; his eyes were sunken; he had lost 20 pounds. His skin had erupted in scaly patches of red and white, later diagnosed as “general dermatitis,” a condition that was undeniably stress-related. During his last days at sea, he had tried to soothe the spreading rash by standing on the bridge, exposed to the sun and air, dressed in nothing but his “skivvies,” but to no avail. The painful condition had made it increasingly difficult for him to sleep, and a sleep-deprived admiral was not the man to lead the navy’s few remaining carriers into the most important battle of the war. Halsey had carried the burden of seagoing command too long without a break, and Nimitz ordered him to the naval hospital. He would miss the Battle of Midway while confined to a hospital bed, his body smeared with a medicinal ointment. It was, he would later remember, “the most grievous disappointment of my career.”
Nimitz downplayed Halsey’s condition in his report to the COMINCH. “He is in the best of spirits, full of vim and vigor, and anxious to get going,” he wrote King on May 29. “But he does need a short period of rest. He is neither ill nor on the sick list.”
On May 28, Admiral Frank Jack Fletcher was notified that he would retain command of Task Force 17. With Halsey laid up, he would be the ranking admiral afloat. But another flag officer would have to step into Halsey’s shoes as commander of Task Force 16. Halsey recommended Rear Admiral Spruance, commander of the task force’s cruiser division. Nimitz, who shared Halsey’s high opinion of Spruance, agreed without hesitation. Spruance was a “black shoe” admiral, but he would retain Halsey’s first-rate staff, and he was well practiced in carrier operations. Indeed, Nimitz had already tapped Spruance as his next chief of staff, and planned to bring him on in that capacity immediately after the forthcoming battle.
Spruance and Halsey were as different as it was possible for two career naval officers to be. Spruance was soft-spoken, prudent, a listener who distrusted rhetoric and never strived for dramatic effect. He led through example and through the quiet projection of confidence and competence, never allowing excitement or emotion to influence his decisions. He tried to avoid reporters, and when he could not av
oid them he gave them nothing remotely interesting or quotable. Halsey was gruff, blunt-spoken, and swaggering, and when addressing the press or the men under his command he could not resist colorful bombast. Yet Halsey and Spruance had been personally close since the early 1920s, when they had served together in the Pacific Destroyer Force. Their wives, Fanny and Margaret, had become good friends during that period, when both families were stationed in San Diego. Their sons, Billy and Edward, were the same age and had been inseparable childhood playmates.
Spruance had been born into a wealthy Baltimore family, and had lived the first years of his life in a mansion. But his family was bankrupted while he was still a boy, and he was packed off to Indianapolis to live with two aunts. He applied to the Naval Academy because his family could not afford to send him to college. He had not liked the academy at all, regarding it as a hidebound, narrow-minded institution in which poorly qualified instructors emphasized rote memorization of technical details, and in which barbaric hazing rituals were tolerated as character-building exercises. He graduated in 1906, ranked 26th in a class of 209. The Lucky Bag called him a “shy young thing with a rather sober, earnest face and the innocent disposition of an ingénue. . . . Would never hurt anything or anybody except in the line of duty.”