On December 31, 1941, Chester William Nimitz took command of the Pacific Fleet, still reeling from the shock of Pearl Harbor. He had no way of knowing where the Japanese would strike next, whether his handful of carriers could stop them, or which of his officers remained trustworthy. Over the next three years, three situations tested the most important quality of his position: making decisions under uncertainty. One involved a dispute between codebreakers and Washington.

Another required relieving a friend while the fate of Guadalcanal hung in the balance. The last meant choosing which Japanese fortresses he would never attack at all. None of these decisions guaranteed victory. Any of them could have failed.

Each reveals how Nimitz actually led the fleet through the darkest months of the Pacific War. Pearl Harbor was still smoking when the man chosen to bear its responsibility arrived to raise his flag. Nimitz, a quiet submarine officer from the hills of Fredericksburg, Texas, traveled across the country in civilian clothes to avoid attention. He left Washington with direct orders from President Roosevelt to take command of the Pacific Fleet and remain in Hawaii until victory over Japan.

At the airfield, he was driven straight to the submarine base, where a small group of officers who had held the fleet together since the attack three weeks earlier received him. For the change-of-command ceremony, Nimitz chose the submarine USS Grayling, moored alongside a pier. It was not a coincidence. Nimitz wore the submarine insignia himself as a young officer, had commanded the USS Snapper before World War I, and understood the trade in a way few commanders of his generation did.

There, before a handful of officers and without the press present, he read his orders aloud and raised his four-star flag on a submarine barely large enough to hold the ceremony. Around him, the scale of the loss was visible in every direction. Eight battleships had been damaged, 188 American aircraft destroyed, most on the ground before they could take off, and another 159 damaged. There were 2,403 American dead, most of them sailors trapped inside the ships he could see from the pier.

The Arizona had been torn apart by the explosion of her forward magazine, and her wreckage still burned in the shallow water. The Oklahoma lay capsized. California and West Virginia had settled into the mud. Nevada had been run aground to keep her from blocking the channel.

Nimitz gave no speech, made no promises of quick revenge. While Douglas MacArthur in the Philippines was already cultivating a public persona, Nimitz intended to lead through paperwork, conferences, and careful judgment of the men around him. In his first hours after raising his flag, he did not begin planning an offensive. He began by asking who in his new staff truly understood the enemy he had just inherited.

The men who had been working at Pacific Fleet headquarters in the final days of 1941 expected to be fired. Admiral Husband Kimmel, the previous fleet commander, had already been relieved and would soon face investigation. In the Navy, when a commander falls, his men usually follow. Nimitz did the opposite.

In one of his first acts, he called the senior members of Kimmel’s staff into his office and told them plainly that he trusted them completely and intended to keep them in their posts. Among those he kept was Captain Charles McMorris, the fleet war plans officer, whose prewar assessments had underestimated the Japanese threat and who might have expected dismissal. Also retained was the intelligence officer, Commander Edwin Layton, who read Japanese and had studied the Imperial Navy since a prewar tour as assistant naval attaché in Tokyo. Layton knew his Japanese counterpart, Admiral Isoroku Yamamoto, personally.

Nimitz was already making a quieter second decision that would matter even more. Down a concrete stairway, in the basement of the administration building at the submarine base, a small and secret unit worked. Officially designated the Combat Intelligence Unit of the Fourteenth Naval District, it was known within the Navy by the code name Station HYPO. Its commander was Commander Joseph Rochefort, a thin, unconventional Californian who had learned Japanese during duty in Tokyo and spent most of his career in the exacting craft of naval codebreaking.

Rochefort ran his operation wearing slippers and a red smoking jacket against the cold of the air conditioning that protected the IBM punch-card machines. He and roughly 140 officers, clerks, radio operators, and civilian analysts—including a group of former musicians from the sunken battleship California who had been retrained as code clerks—worked twelve-to-eighteen-hour shifts in that windowless room, sorting through thousands of intercepted Japanese radio signals encrypted in a naval operations code the Americans called JN-25. The code was a super-enciphered five-digit system. Each intercepted signal was a piece of a puzzle no American could see in full.

Rochefort’s team had been working on successive versions of JN-25 for over two years. Nimitz gave Layton and Rochefort priority. He ordered that preliminary intelligence assessments from HYPO be brought to him personally every morning before operational briefings, and directed that Layton have access to him whenever new information appeared. In Washington, senior officers in the Navy’s central codebreaking organization, OP-20-G, viewed HYPO with jealousy and often open suspicion.

Nimitz was choosing to trust the men in the basement at Pearl Harbor rather than the offices in the capital. It was a small decision made in the first weeks of 1942, and it was the first of the three moments on which this story is built. During the early months of that year, the news from every direction grew worse. Wake Island fell on December 23, 1941.

Guam was already lost. Hong Kong surrendered on Christmas Day. In Malaya, the British battleship Prince of Wales and battlecruiser Repulse were sunk by aircraft on December 10, 1941. Singapore fell on February 15, 1942, and 80,000 British, Indian, and Australian troops became prisoners of war.

In the Philippines, MacArthur’s men were retreating to the Bataan Peninsula, which would surrender in early April, followed by the fall of Corregidor in May. In the Dutch East Indies, an Allied naval force was destroyed at the Battle of the Java Sea at the end of February, and the great oil fields of Sumatra and Borneo passed into Japanese hands. Nimitz had almost nothing with which to respond. His entire striking force in the central Pacific depended on three carriers that had been at sea when the bombs fell on Pearl Harbor.

By spring 1942, the analysts at Station HYPO could read enough of JN-25—perhaps ten to fifteen percent of messages in any given intercept—to assemble the outlines of Japanese fleet movements. The first real test came in early May 1942. Layton warned Nimitz that the Japanese were moving to seize Port Moresby on the southern coast of New Guinea, a step that would threaten Australia and the supply lines carrying American reinforcements. Nimitz sent Rear Admiral Frank Jack Fletcher with the carriers Yorktown and Lexington to intercept them.

What resulted, from May 4 to 8, was the Battle of the Coral Sea, the first naval battle in history fought entirely between carriers, with the surface ships of the two fleets never sighting each other. The Americans lost the Lexington to a series of torpedo hits and internal fuel-vapor explosions. The Yorktown took one 250-kilogram bomb that penetrated five decks and killed 37 men, but damage control parties brought the fires under control within hours. The Japanese lost the light carrier Shoho, and the carrier Shokaku was heavily damaged, while her sister Zuikaku’s air group was destroyed.

Neither Shokaku nor Zuikaku was available for the operation being planned in Tokyo. That operation was far larger than Coral Sea. Rochefort began to discern its outline from intercepted messages, and what he saw alarmed him. By mid-May 1942, Station HYPO was extracting intelligence from Japanese naval frequencies indicating something on a scale the Americans had never seen.

Admiral Yamamoto was massing nearly his entire naval force for one decisive operation. Four carriers of Vice Admiral Chuichi Nagumo’s First Air Fleet; battleships, including his flagship Yamato, the largest battleship ever built; cruisers; destroyer screens; troop transports; tankers; and a separate diversionary force under Vice Admiral Boshiro Hosogaya aimed at Attu and Kiska in the far northern Aleutians. The target was a location the analysts could see only under the two-letter designator “AF. ” Rochefort was convinced “AF” meant Midway.

Navy intelligence in Washington disagreed. The influential Redman brothers argued that AF might be somewhere else entirely. Rochefort proposed a test. He recommended that the small garrison at Midway be directed to send a message in plain English, unencrypted, on a frequency known to be monitored by the Japanese, stating that the island’s freshwater distillation plant had broken down and that Midway was short of drinking water.

Nimitz approved. Midway sent the message. Within a short time, HYPO intercepted a Japanese naval signal, properly encrypted in JN-25, reporting that AF was short of fresh water and that any occupation force sent to seize the island should be prepared accordingly. The ruse had worked.

AF was Midway. Nimitz backed Rochefort completely. The Japanese target was Midway. The blow would come in the first week of June 1942.

The American carriers would be there waiting. By making that decision, Nimitz gave himself the only advantage Yamamoto never imagined the Americans could possess. For the first time since December 7, the smaller force would be the one setting the ambush. But knowing where the enemy was coming from was not the same as knowing how to stop him.

Nimitz still had to defend a tiny atoll against a fleet twice the size of his own, with two carriers he could rely on and one that most of his engineers said would not sail for weeks. Vice Admiral William Halsey, the aggressive carrier commander who by law should have led Task Force 16, was in no condition to sail. Weeks of continuous operations had left him suffering from a severe skin condition, unable to sleep and down more than twenty pounds. Nimitz took one look at him and ordered him to the hospital immediately.

Before leaving, Halsey recommended the man he trusted to replace him: Rear Admiral Raymond Spruance, commanding the cruiser screen of Task Force 16 aboard the heavy cruiser Northampton. Spruance was not an aviator. He was cool, precise, analytical, and trusted by Halsey’s airmen. Nimitz accepted the recommendation without hesitation.

The Yorktown was the question mark. When she limped back to Pearl Harbor from the Coral Sea on May 27, 1942, yard workers estimated proper repairs would take two weeks to three months. Nimitz did not have weeks. He told them they had 72 hours.

What followed inside the big dry dock at Pearl Harbor was one of the most remarkable feats of industrial labor in the entire Pacific War. More than 1,400 civilian workers and Navy yard men swarmed over the carrier around the clock in three shifts, working under floodlights, welding hull plates, shoring bulkheads, replacing frames, patching the flight deck, and repairing the electrical and fire-control systems destroyed by the bomb. They cut power to the civilian city of Honolulu to supply the dry dock. They worked from the ship’s original construction drawings because there was no time to draft proper repair plans.

Within roughly 65 hours, the Yorktown was floated and made ready for sea. She sailed out of the harbor on May 30, 1942, still carrying welding crews finishing their work below decks. The Japanese, from the damage they had inflicted at Coral Sea, concluded that Yorktown had either sunk or was out of the war for months. They planned Operation Midway believing they would face at most two American carriers.

In fact, they would face three. On May 27, 1942, the day Yorktown arrived for her miracle repair, Nimitz issued Operations Plan 2942. In it, he instructed his commanders to be guided by what he called the principle of calculated risk. Simply put, he told them not to throw their irreplaceable carriers against a superior enemy force unless there was a good chance of inflicting greater damage in return.

This was not caution; it was calculation. Nimitz understood something Yamamoto never fully grasped. American shipyards could replace a lost carrier in time. Japanese shipyards could not.

The three American carriers were the last line of defense for Hawaii and the West Coast, and they had to fight hard, but intelligently, and never sacrifice themselves in a hopeless exchange. Task Force 16 under Spruance sailed with Enterprise and Hornet on May 28. Task Force 17 under Fletcher sailed with the still-smoking Yorktown on May 30. The two forces met northeast of Midway at a point in the empty ocean the staff had grimly named “Point Luck.

” From there, about 325 miles from the atoll, they waited on the flank of the advancing Japanese in a stretch of sea the enemy had no reason to search. On the morning of June 4, 1942, the trap closed. Nagumo’s four carriers—Akagi, Kaga, Soryu, and Hiryu—launched their first strike against Midway itself, exactly as Station HYPO had predicted. One hundred eight aircraft crossed the atoll in a coordinated attack, bombing fuel stores, destroying the seaplane ramp, killing men in the barracks, and setting fire to the oil supplies.

But the Marine defenders, warned in advance, had gotten every flyable aircraft off Midway before the Japanese arrived. The strike leader reported that a second strike would be necessary. That single radio message triggered the tactical decision that decided the battle. Before that report arrived, before any reliable news reached Nagumo about American carriers, he had already ordered his reserve strike aircraft.

They had been held in readiness in case American ships appeared. They were being rearmed from anti-ship weapons for a second attack on Midway, their torpedoes lowered to the magazines, their armor-piercing bombs taken off their racks. The scout plane that found the American carriers eastward reported only after Nagumo had already begun the rearming. He was forced to reverse the process.

Bombs were unloaded. Torpedoes and armor-piercing weapons were called back up. Aircraft stood half-armed in the hangars while crews raced to change their loads. The recovery of the returning strike aircraft, low on fuel, compounded the chaos.

The flight decks were crowded. The hangars were crowded. Bombs were left stacked on the deck instead of being properly stowed. For about an hour that morning, the four Japanese carriers were floating powder kegs.

The American torpedo squadrons attacked first. Torpedo Squadron Eight from Hornet, led by Commander John Waldron, was almost entirely wiped out without scoring a single hit. Of fifteen Devastator torpedo bombers that launched, none returned. One pilot, Ensign George Gay, survived and spent the day in the water watching the battle unfold above him.

They were followed by Torpedo Six from Enterprise and Torpedo Three from Yorktown, slaughtered in turn by the Japanese Zero fighter cover. Of 41 American torpedo planes that participated that morning, only six returned, and none of their torpedoes hit. It was the worst massacre of a naval aviation unit in the war, but their sacrifice was not in vain. Their attacks pulled the Zeros down to sea level, and above the Japanese carriers, by a rare stroke of fortune, the dive bombers from Enterprise led by Wade McClusky and from Yorktown led by Maxwell Leslie arrived to attack a fleet with no air cover.

McClusky had been on the verge of turning back. His squadrons had reached their fuel limit and found an empty ocean. He continued northwest on a hunch, following the track of the Japanese destroyer Arashi, which was rushing to rejoin the fleet after attacking an American submarine. The Arashi’s course led him directly to Nagumo.

In roughly six minutes between 10:22 and 10:28 a. m. , Kaga, Akagi, and Soryu were hit almost simultaneously. The bombs penetrated the crowded flight decks and exploded among the fueled aircraft and unstowed ordnance below.

Fires broke out in the hangars. Ammunition began to explode in secondary blasts that ran the length of the ships. The three big carriers turned into burning wrecks within minutes, destined to sink or be scuttled before the end of the day. The fourth carrier, Hiryu, operating in a slightly separate position to the north, survived long enough to strike back.

Her aircraft found Yorktown and hit her with three bombs and then two torpedoes. Yorktown lost power, listed heavily, and her crew was forced to abandon her. Her air group, which had launched before she was hit, landed on Enterprise and Hornet, and the surviving pilots joined the pursuit of Hiryu. Late that afternoon, dive bombers from Enterprise and the displaced Yorktown air group found Hiryu and left her burning as well.

She was scuttled by her destroyers before dawn. But the Yorktown’s story was not over. Fires were brought under control overnight, and salvage teams returned aboard the next day. Tow lines were secured, and she began a slow tow toward Pearl Harbor.

On June 6, 1942, the Japanese submarine I-168 penetrated the screen and fired torpedoes into her hull, with a third torpedo hitting the escorting destroyer USS Hammann. Hammann broke in two and sank in four minutes, taking most of her crew with her. Yorktown stayed afloat through the night. At dawn on June 7, 1942, she finally rolled over and sank.

By the end of the battle, the four fleet carriers that had led the attack on Pearl Harbor six months earlier were completely destroyed. With them, Japan lost all 248 of their aircraft and roughly 110 trained aircrew killed. The irreplaceable immediate loss at Midway was the four carriers themselves. More than three-quarters of the naval aviators aboard those ships survived and continued fighting in later campaigns.

The pilot crisis that ultimately crippled Japanese carrier aviation built up over the following eighteen months in the grinding attrition of the Solomon Islands and the Rabaul air campaigns, where the aviators evacuated from the burning carriers were expended alongside hastily trained replacements who could not match their skill. Midway broke the back of the fleet. The slow attrition of the pilots came later. Yamamoto called off the operation and turned his fleet for home.

The victory at Midway was won by the ambush, by the codebreaking that Nimitz had trusted, by the sacrifices of the torpedo squadrons, and by six minutes of dive-bomber attacks executed with coordination the men who flew them could never have managed if they had tried. It was the turning point of the naval war in the Pacific. But victory at sea did not automatically translate into control of the ground, and the next test came in the Solomon Islands. On August 7, 1942, the First Marine Division under Major General Alexander Vandegrift landed on a malaria-ridden island called Guadalcanal in the southern Solomons, seized a half-completed Japanese airstrip, and renamed it Henderson Field after Major Lofton Henderson, a dive-bomber pilot killed at Midway.

The landing was the easy part. What followed was six months of brutal fighting on the island, in the air above it, and in the black waters around it, as both sides pushed forces to hold or retake the airfield. The sea approaches to Guadalcanal became a killing ground. On the night of August 8–9, 1942, a Japanese cruiser force of seven ships under Vice Admiral Gunichi Mikawa slipped through the slot between the islands undetected until too late, and in 32 minutes of gunfire and torpedoes at close range off Savo Island, sank four Allied heavy cruisers and damaged a fifth.

Nearly 1,000 Allied sailors died. It was the worst open-water defeat ever suffered by the United States Navy. Mikawa withdrew without pressing the attack to destroy the vulnerable American transports still unloading off the beaches. The transports departed the next day, carrying away much of the Marines’ equipment, leaving Vandegrift’s men on short rations for weeks.

During the following months, the USS Wasp was torpedoed and sunk by the Japanese submarine I-19 in September 1942. The USS Hornet was sunk on October 26, 1942, at the Battle of Santa Cruz. For several weeks in late 1942, the United States Navy had only one operational carrier in the Pacific: the Enterprise, sailing patched and welded with a hole in her flight deck. So many warships from both fleets had gone to the bottom of the channel northwest of Guadalcanal that sailors gave it a name that stuck: Ironbottom Sound.

The campaign was consuming ships, aircraft, and men at a rate neither side had planned, and by the fall of 1942, the outcome was genuinely in doubt. At the heart of American difficulties was a command problem. The officer in charge of the South Pacific area, Vice Admiral Robert Ghormley, was a capable, intelligent naval officer with a good record of administrative service, but the strain of the campaign had worn him down. Operating from his headquarters at Noumea in New Caledonia aboard the old repair ship USS Argonne rather than ashore, he had become cautious and pessimistic, hoarding scarce resources rather than using them.

On October 16, 1942, Ghormley reported to Washington that the forces available to him were, in his words, “entirely inadequate to meet the situation. ” Nimitz had already gone to sea himself. He had flown to Noumea in the last week of September and spent a day with Ghormley reviewing the situation. Then he flew to Guadalcanal on September 30 to inspect the Henderson Field perimeter with Vandegrift.

He talked with battalion officers, ate a Marine field ration, and spent the night within range of mortar and naval gunfire. He returned to Pearl Harbor on October 5 and thought about the problem for nearly two weeks. Then he made the second of his three decisions. On October 18, 1942, Nimitz relieved Ghormley of command and placed Vice Admiral William Halsey, recovered from his illness, in charge of the area.

It was a painful order to sign. Ghormley was an old friend from the Naval Academy, had committed no disgraceful act, and had not lost the campaign. But Nimitz judged that the campaign needed a fighter more than an administrator, and Halsey was the most aggressive fighting admiral in the Pacific. Word of Halsey’s arrival spread among the men on Guadalcanal within 48 hours, and the effect on morale was immediate.

Halsey had no intention of directing the battle from a repair ship in the harbor. He went ashore, walked the airfield, met Vandegrift, and promised the Marines they would stay on the island. Within days, ships that had been held back began moving forward. The injured USS South Dakota, restored from earlier battle damage, was ordered south.

The old carrier Enterprise, still with a hole in her deck, was ordered south with her. A new pulse entered the war in the South Pacific. This change was tested almost immediately. In mid-November 1942, the Japanese launched their most ambitious attempt of the campaign, sending a battleship force to bombard and destroy Henderson Field while pushing a convoy of eleven troop transports laden with reinforcements to retake the island.

What followed, over the nights of November 12–15, 1942, was one of the fiercest naval battles of the entire war, fought mostly in the dark at close range in Ironbottom Sound. On the night of November 12–13, an American force of five cruisers and eight destroyers under Admirals Daniel Callaghan and Norman Scott collided head-on with the Japanese bombardment group in a chaotic, brawling engagement at such short range that some American ships fired their guns at near-zero elevation. Both American admirals were killed on the bridges of their ships within minutes of each other. The Japanese battleship Hiei was heavily damaged and finished off the next day by aircraft from Henderson Field and the Enterprise.

Then on the night of November 14–15, Admiral Willis Lee took the new battleships Washington and South Dakota into Ironbottom Sound. The engagement began badly. The four American destroyers screening the battleships were quickly destroyed by Japanese destroyers and light cruisers. South Dakota lost electrical power at a critical moment and took 26 hits, silhouetted by Japanese star shells as a target in a shooting gallery.

She survived because the Washington, tracking the Japanese battleship Kirishima through her SG surface-search radar in the darkness, opened fire from a range of about 8,400 yards. In seven minutes, she put an estimated nine 16-inch shells and dozens of 5-inch shells into the Japanese battleship, wrecking her hull, jamming her rudder, and setting fires her crew could not extinguish. Kirishima capsized and sank in the early hours of November 15, the first major Japanese warship sunk by American surface gunfire. The Japanese called off the bombardment and turned back.

The reinforcement convoy was destroyed. Attacked by aircraft all day on November 14, seven of the eleven transports were sunk before reaching the island. Only four made it through, and their commander, Admiral Raizo Tanaka, ordered them beached at Tassafaronga for lack of any other way to unload under American guns. American planes strafed them in daylight as they lay there.

Of roughly 10,000 Japanese troops who sailed with the convoy, about 2,000 reached the island. Henderson Field held. The fighting on Guadalcanal ended quietly in early February 1943. In Operation Ke, the Japanese used destroyers on the nights of February 1, 4, and 7 to evacuate more than 10,000 surviving troops.

American intelligence, which had read Yamamoto’s intentions the previous spring, missed the withdrawal entirely. The campaign in the Solomons continued to grind up the chain toward Bougainville and Rabaul, but the great question of whether the Japanese advance could be stopped had been answered. The new question was harder. The map of the central and western Pacific was a scattering of hundreds of islands and atolls, and the Japanese had spent much of the previous decade turning many of them into fortresses.

Kwajalein, Eniwetok, Truk, Ponape, Saipan, Tinian, Guam, Peleliu, Yap, the Bismarck barrier, and every mandated territory Japan had held since 1919. American planners in Washington, calculating a strategy of capturing every island in sequence and destroying every Japanese stronghold in turn, projected hundreds of thousands of American casualties and a war delayed for years. The debate over how to advance split along familiar lines. General Douglas MacArthur, running the Southwest Pacific area from Australia, insisted the road to Tokyo ran through the Philippines and along the New Guinea coast.

Admiral Ernest King, Chief of Naval Operations in Washington, wanted a direct drive through the central Pacific from Hawaii, using the fast carriers as a mobile striking force. Nimitz balanced both options and pressed for a middle course, accepting the value of the parallel advance MacArthur proposed. A two-axis offensive would force the Japanese to divide their remaining strength. At the Trident Conference in Washington in May 1943, the Joint Chiefs agreed to the two-axis strategy, and command of the central Pacific campaign went to Nimitz.

The third moment in Nimitz’s story was not the invention of island hopping itself. It was the bold application of that allied strategy of selective advance and bypass in the central Pacific, on a scale and at a speed few contemporaries dared. The idea, as Nimitz applied it, was to stop trying to capture every Japanese stronghold. Instead of destroying every fortress in sequence, the Americans would identify the specific islands necessary for the next leap—those with harbors and flat land suitable for airstrips within range of the next objective—and take only those.

The major garrisons between them, some containing tens of thousands of elite Japanese troops, would be bypassed. American naval and air power would cut their supply lines, isolate them within a moving perimeter, and simply leave them behind the lines. The phrase used in planning documents was that these bypassed positions would be left to wither on the vine. A strong garrison on an island that could not be reinforced, fed, or sortied to fight was no longer a strategic factor.

It was a prison without walls. The logic was sound on paper, but the decision required something hard from the commander who signed it. It meant deliberately leaving armed enemy divisions intact behind the advancing front, trusting that control of the sea and air would render them harmless. Nimitz accepted the risk.

The first major test of the central Pacific campaign came in November 1943 at Tarawa Atoll in the Gilbert Islands. The objective was a small, flat islet called Betio, about two miles long and 800 yards wide at its widest point, containing a Japanese airstrip and a garrison of about 4,500 men, including 2,600 combat troops of the Special Naval Landing Force. It took the Second Marine Division about 76 hours. The price was appalling.

The preliminary naval bombardment was shorter and less accurate than the beach required. The air support was poorly coordinated. Radio communications collapsed early. The Japanese defenses were far more sophisticated than planners had estimated.

About 1,009 Marines were killed and nearly 2,300 wounded in three days of fighting for a piece of ground smaller than many American airfields. Of the Japanese garrison, only 17 soldiers survived to be captured, along with about 130 Korean laborers. The photographs that came back from Tarawa of American dead floating in the shallow water and lying in rows on the sand shocked the American public more than any previous engagement in the Pacific, and the lessons paid for at Betio were absorbed almost immediately. When American forces attacked Kwajalein Atoll in the Marshall Islands from January 31 to February 3, 1944, the preparatory bombardment was far longer and heavier, the landing craft were available in numbers and newer models, and communications were reorganized.

Kwajalein fell in four days at a fraction of the cost, and the subsequent operation against Eniwetok was moved up and executed in mid-February with even lower losses. The next demonstration proved the doctrine in its harshest form. Ahead lay Truk in the Caroline Islands, the great Japanese fleet anchorage in the central Pacific, a lagoon surrounded by towering volcanic islands and protected by coastal batteries and airfields. American planners had long assumed Truk must be stormed at enormous cost, and the base bore the nickname “Gibraltar of the Pacific.

” On February 17 and 18, 1944, Nimitz sent Rear Admiral Marc Mitscher and the fast carriers of Task Force 58 to strike Truk from the air in an operation called Hailstone. In two days of raids, the carrier air groups sent about 40 Japanese ships to the bottom of the lagoon and destroyed about 270 Japanese aircraft. Then, on March 12, 1944, Nimitz officially directed that Truk be bypassed. It was one of the shortest and most consequential orders of his command.

The great fortress would never be stormed at all. American air power would keep the base neutralized with periodic raids for the rest of the war, and more than 50,000 Japanese soldiers and airmen on the atoll would remain out of the conflict, short of food, planting gardens in the coral, waiting for a battle that never came. The fortresses were left to wither on the vine, exactly as the theory promised. Behind that decision, the offensive continued.

On June 15, 1944, American forces landed on Saipan in the Marianas. The Marianas were the real prize, and the reason was measured in nautical miles. From airfields on Saipan, Tinian, and Guam, the new Boeing B-29 Superfortress, with a combat range of more than 1,500 miles, could reach the Japanese home islands themselves. Japan recognized the stakes and pushed its last naval air strength to stop the landings.

On June 19 and 20, 1944, Admiral Raymond Spruance’s Fifth Fleet met Vice Admiral Jisaburo Ozawa’s carriers west of the Marianas in the largest carrier battle of the war, the Battle of the Philippine Sea. The result was catastrophic for Japan. American Hellcat fighters and antiaircraft fire shot the Japanese air groups out of the sky at such a rate that American pilots named the day itself. They called it the “Great Marianas Turkey Shoot.

” On June 19, Japan launched four separate raids totaling more than 300 aircraft and lost more than 300 aircraft within about eight hours. Most were shot down by Hellcats directed by American radar and fighter direction officers using techniques developed since Guadalcanal. Some planes were lost with the carriers Taiho and Shokaku, torpedoed by the American submarines Albacore and Cavalla and sinking later due to internal explosions of leaking aviation fuel vapors. American losses that day were about 30 aircraft.

On June 20, in a long-range strike at the very limit of fuel that Mitscher ordered knowing many of his pilots would not return in the dark, the American air groups sank the carrier Hiyo, damaged two others, and finished off the last trained Japanese pilots as an effective force. Mitscher ordered his ships to turn on their lights that night, defying strict rules against showing lights in submarine-infested waters, to guide his exhausted pilots home. About 80 American aircraft ditched in the ocean after running out of fuel. Most of their crews were rescued.

American losses were 123 aircraft and about 100 aircrew. Japanese losses that day were nearly 100 aircraft and the carrier of the Third Fleet. The Japanese carrier air arm was finished. The remaining Japanese carriers would sail again in October at Leyte Gulf, but they would sail with nearly empty flight decks, used as decoys rather than a striking force, and would be sunk off Cape Engano at the end of that month without launching a single coordinated strike against an American ship.

Saipan was secured on July 9, 1944, Tinian on August 1, and Guam on August 10. Navy construction battalions moved in and began building the airfields. On November 24, 1944, more than 100 B-29s took off from Isley Field on Saipan and bombed Tokyo for the first time from the Marianas. The great bomber offensive that would level Japan’s industrial areas over the following nine months began from runways built on islands captured because the strategy Nimitz supported made them reachable.

The B-29 raids from the Marianas eventually reached every major Japanese city, culminating in the firebombing raids from March to July 1945 and the two atomic bomb missions of August 6 and 9, 1945, which took off from Tinian with aircraft of the 509th Composite Group. On September 2, 1945, on the deck of the American battleship Missouri in Tokyo Bay, Fleet Admiral Chester William Nimitz signed the Japanese surrender document on behalf of the United States. Above him flew the flag that had flown over the Washington Navy Yard on December 7, 1941, brought specifically for the occasion. Around him stood representatives of the Allied nations, the officers of his fleet, and a small delegation of Japanese officials led by Foreign Minister Mamoru Shigemitsu and General Yoshijiro Umezu.

The ceremony took 23 minutes. When it ended, hundreds of American aircraft flew overhead, and the war in the Pacific was officially over. These three decisions show why Nimitz mattered at critical moments, but they did not win the Pacific War by themselves. The war in the Pacific was won by an American war economy that produced ships and aircraft in numbers no other nation could match, with 17 fleet carriers, nine light carriers, and dozens of escort carriers launched between 1943 and 1945.

It was won by the submarine campaign that sank by the end of the war more than half of the Japanese merchant fleet, depriving the home islands of the oil, rubber, and rice on which their industrial and military survival depended. It was won by the Army and Marine divisions on the beaches from Guadalcanal to Okinawa, by the Army Air Forces bombers over the home islands, by the Australian, New Zealander, and British forces in the southwest Pacific, and by the armies of China that pinned down more than a million Japanese soldiers on the Asian mainland. What Nimitz contributed to this larger effort in the moments this story has followed was a specific kind of judgment, applied when the cost of a wrong answer was prohibitive. He trusted the men in the Pearl Harbor basement, turning a decoded radio message into an ambush that destroyed four Japanese carriers in a single afternoon.

He relieved a friend he respected in the middle of a losing campaign and replaced him with a fighter who held the line at Guadalcanal. When the choice in the central Pacific came between grinding down every Japanese fortress one by one or applying a broader strategy of selective advance, he chose the harder and faster path, accepting the risk of leaving armed enemy divisions intact behind him. That is why these three moments are still taught in war colleges: not because they alone won the war, but because they show, more than any other moments in his command, how a commander in a brutal war keeps a clear head and makes the decisions the moment requires.