The admiral who warned Japan against attacking America had a secret: he knew America too well. In 1940, Admiral Isoroku Yamamoto stood before Japan’s …

The admiral who warned Japan against attacking America had a secret: he knew America too well. In 1940, Admiral Isoroku Yamamoto stood before Japan's ...

On the morning of September 1940, Admiral Isoroku Yamamoto stood before the Japanese Naval General Staff and delivered a warning no one in the room wanted to hear. If ordered to fight, he said, he would run wild for the first six months or a year, but he had absolutely no confidence in the second or third year. Fifteen months later, the Z signal flag rose over his flagship Akagi off the coast of Hawaii. Six months after that, the sea delivered its verdict on his warning.

Thumbnail

Yamamoto had been right with almost month-perfect precision. This is the story of the most expensive strategic miscalculation of the twentieth century, when a disciplined, intelligent, and powerful military convinced itself that a nation of assembly-line workers and small shopkeepers simply lacked the will to fight. By the fall of 1940, the men who ruled imperial Japan had settled on a set of assumptions about the United States that would lead them step by step into a war they could not win. At the heart of that thinking stood Admiral Osami Nagano, soon to become chief of the Naval General Staff, and General Hideki Tojo, then serving as war minister.

Both men shared a conviction that had crystallized over four decades of Japanese military success: spirit could overcome steel. That belief rested on three pillars. The first was bushido, the warrior code inherited from the samurai tradition, alongside the broader concept of Yamato-damashii, the Japanese spirit. Japanese soldiers were taught that death in battle was preferable to the shame of surrender, and their planners assumed American soldiers lacked an equivalent code.

Americans, in this view, would fight only while fighting was easy and profitable, and would collapse once casualties mounted. The second pillar was the memory of the Russo-Japanese War of 1904 and 1905. A generation earlier, Japan had crippled the Russian Pacific Fleet with a surprise attack on Port Arthur, then annihilated the Baltic Fleet at Tsushima after its 18,000-mile voyage around the world. The lesson Nagano and his colleagues drew was simple: a larger, richer, more populous opponent could be forced to the negotiating table by a swift and painful first blow.

The third pillar was a specific image of America itself. Japanese intellectuals and officers described the United States as a country of ethnic and religious factions lacking common purpose, a democracy paralyzed by public opinion, a society of moviegoers and car buyers with no tradition of collective sacrifice. American isolationism was cited as proof. The America First movement, Congress’s reluctance to expand the army, and the lingering memory of World War I all seemed to confirm that a Pacific war fought thousands of miles from the American mainland would not sustain popular support.

Not every senior Japanese officer accepted this picture. The most important dissenter was Yamamoto himself. He knew America well. From 1919 to 1921 he studied at Harvard, and from 1926 to 1928 he served as naval attaché in Washington.

During those years he traveled the country by train. He toured the great Ford assembly plants in Detroit, where cars rolled off the lines by the thousands, and visited the oil fields of Texas, where drilling rigs stretched from horizon to horizon. He played poker with American officers and learned, as he later put it, when a man was beaten and when he was bluffing. Everything he saw convinced him his colleagues in Tokyo were wrong.

The cheerful, unpretentious Americans he met at diplomatic dinners and in train cars were not weak. They were citizens of a continental industrial power whose potential strength exceeded everything Japan could hope to muster. The car factories he toured could be converted to tank factories. Texas oil could fuel fleets larger than the Combined Fleet.

He said so plainly. Anyone who had seen Detroit and Texas, he told fellow officers, knew Japan lacked the national strength for a naval race with America. On January 24, 1941, Yamamoto put his reasoning in a letter to political activist Ryuichi Sasakawa. To win a war against the United States, he wrote, it would not be enough to seize Guam and the Philippines, nor even Hawaii and San Francisco.

To guarantee victory, Japanese armies would have to march to Washington and dictate terms from inside the White House itself. He did not mean this as bravado but as a proof of impossibility. A full invasion of the American continent was obviously impossible. Therefore total victory was impossible.

Therefore war should be avoided. His warnings were not welcome. Ultranationalists in the army had already assassinated politicians and business leaders they considered too soft on the West, and Yamamoto received death threats. Partly to protect him and partly to remove him from Tokyo’s political debate, his superiors appointed him commander in chief of the Combined Fleet in August 1939 and sent him to sea.

The political ground under him shifted throughout 1941. On July 26, in response to the Japanese occupation of southern French Indochina, the United States froze Japanese assets and imposed the oil embargo Tokyo had long feared. Japan imported about 80 percent of its oil from American sources. Without those imports, the Imperial Navy could operate its fleet for roughly a year and a half before its fuel tanks ran dry.

Prime Minister Prince Fumimaro Konoe, who had led the government since July 1940, tried to open a direct channel to Washington. Through the summer and early fall of 1941 he pushed for a personal summit with President Franklin Roosevelt, hoping a face-to-face meeting might produce concessions from both sides. General Tojo, his army minister, refused to approve any withdrawal from China. Without that concession, Roosevelt would not agree to the meeting.

The summit collapsed. On October 16, 1941, Konoe resigned. Two days later, Emperor Hirohito appointed Tojo prime minister. Tojo kept the army ministry for himself.

The government that would lead Japan to war now sat under the direct command of a general who believed morale would decide the battle. On November 5, 1941, an imperial conference held in the emperor’s presence formally approved the path to war. Diplomats were given until the end of November to wring concessions from the Americans. If they failed, hostilities would begin in early December.

One sentence from this period has become legendary and needs correction. In countless documentaries and history books, Yamamoto is quoted after Pearl Harbor as saying Japan had awakened a sleeping giant and filled it with terrible resolve. He never said it. The line was written for the 1970 film Tora!

Tora! Tora! Historians have searched his letters and papers and never found it. What Yamamoto actually wrote in a letter drafted only weeks after Pearl Harbor was quieter and darker.

A military man, he wrote, cannot really be proud of defeating a sleeping enemy. It is shameful. By early November 1941, that shame was only weeks away. Six aircraft carriers of the First Air Fleet under Vice Admiral Chuichi Nagumo were preparing to sail into the empty North Pacific in complete radio silence.

Their target lay nearly 4,000 miles east, where ships rode at anchor in the shallow blue water of a place called Pearl Harbor. At 3:42 on the morning of December 7, 1941, the minesweeper USS Condor spotted a periscope in the restricted waters outside Pearl Harbor. Less than three hours later, the destroyer USS Ward sighted a small Japanese submarine trailing the supply ship USS Antares toward the harbor entrance and sank it with gunfire and depth charges. The reports moved up the chain of command slowly on a peacetime Sunday morning.

No general alert was sounded. At six minutes before eight, the first wave of Admiral Nagumo’s carrier aircraft crossed the Oahu coast at Kahuku Point, split into attack groups, and dropped their bombs. The tactical execution was superb. In less than two hours, 183 aircraft in the first wave and 170 in the second sank or damaged 21 American warships across the harbor.

Along Battleship Row, USS Arizona exploded when a bomb ignited her forward magazine, killing more than a thousand of her crew in an instant. USS Oklahoma capsized. USS California, USS West Virginia, and USS Nevada sank or grounded. More than 2,400 Americans died.

Nearly 200 aircraft were destroyed on the ground at Hickam, Wheeler, and Ford Island. The pride of the American Pacific Fleet burned in shallow water. Nagumo’s officers celebrated on the bridge of the Akagi. Commander Minoru Genda and Captain Mitsuo Fuchida, who had led the air attack, urged Nagumo to launch a third strike.

The battleships had been the assigned targets, but the real strategic prizes lay elsewhere in the base. Four and a half million barrels of fuel oil sat above ground in unprotected storage tanks along the harbor’s edge. The submarine base was intact. Most important, the dry docks and repair facilities of the Pearl Harbor shipyard were untouched.

Nagumo refused. His pilots were exhausted. American aircraft that had survived the first two waves might be waiting. The position of the American carriers remained unknown, and if they appeared, his own carriers could be attacked.

He recovered his aircraft and turned north for the long voyage home. Three decisions made in that harbor set the terms of the war Yamamoto had feared. Nagumo left the fuel intact. He left the dry docks intact.

And through no fault of his own, he missed the American carriers entirely. USS Enterprise was returning from Wake Island. USS Lexington was delivering aircraft to Midway. USS Saratoga was on the West Coast.

None of the three carriers that would lead the counteroffensive across the Pacific was in the harbor that morning. The fuel Nagumo left untouched would power the Pacific Fleet for the next twelve months. The dry docks he spared would return damaged American warships to battle in weeks rather than years. The carriers he never found would face him again in six months at Midway.

The American response moved with a speed no one in Tokyo had anticipated. At 12:30 on December 8, President Roosevelt stood before a joint session of Congress and asked for a declaration of war. His speech took barely seven minutes. Twenty-one minutes after he finished, the Senate voted 82 to 0.

Twelve minutes later, the House voted 388 to 1. The sole dissenting vote came from Representative Jeannette Rankin of Montana, a lifelong pacifist who had also voted against entering World War I, and she was met with hisses from her colleagues. The America First Committee, the largest isolationist organization in the country, dissolved itself within days. Recruiting stations reported lines wrapping around entire blocks.

Within seventy-two hours of the attack, more than a million American men had volunteered for military service. The image of a querulous, divided, comfort-loving democracy that had shaped Japanese planning for years vanished between Sunday morning and Monday evening. Beneath the political response, the industrial transformation had already begun. Ford Motor Company had broken ground the previous spring on a new plant at Willow Run, Michigan, designed to produce B-24 Liberator bombers on a moving assembly line.

Henry Kaiser’s shipyards on the West Coast were preparing to build merchant ships known as Liberty ships using prefabricated welded sections instead of the riveted construction that had defined shipbuilding for a century. Neither program had delivered its first product on the morning of the Pearl Harbor attack. Both would soon produce aircraft and ships at rates no Japanese planner had accounted for. Tokyo did not see this.

What Tokyo saw was an unbroken run of victories. Guam fell on December 10, 1941. Its garrison of about 550 Marines, sailors, and local guards had no artillery or aircraft, only a few rifles. The Marines and civilian construction workers on Wake Island repelled the first Japanese landing attempt on December 11, sinking the destroyers Hayate and Kisaragi in the only successful repulse of a Japanese amphibious operation in the entire opening offensive.

Wake’s defenders held for sixteen days before falling on December 23. The British fortress at Singapore, nicknamed the Gibraltar of the East, surrendered on February 15, 1942. General Tomoyuki Yamashita drove his Twenty-Fifth Army down the Malayan Peninsula on bicycles and took the fortress from the landward side, where its heavy coastal guns were not aimed. About 85,000 Allied and Commonwealth troops laid down their arms.

It was the largest surrender in British military history. In the Philippines, General Douglas MacArthur’s forces fell back to the Bataan Peninsula and then to the fortified island of Corregidor. On April 9, 1942, Major General Edward King surrendered with about 75,000 American and Filipino troops, the largest surrender in American history. The prisoners were forced to march sixty-five miles across the peninsula under a tropical sun and the threat of Japanese bayonets.

Between 5,000 and 18,000 Filipinos and hundreds of Americans died on that march. Corregidor itself fell on May 6. Inside the Naval General Staff in Tokyo, these victories confirmed what senior officers had believed from the start. The Americans and their allies were collapsing.

The ocean Japan had planned to seize was falling into its hands weeks ahead of schedule. Senior officers began speaking of a phenomenon they called senchubyo, victory disease. The original plans had expected to lose up to a quarter of the attacking force in the first assaults. Actual losses had been negligible.

The first crack in that certainty came in the Coral Sea, off the northeast coast of Australia. From May 4 to 8, 1942, an American task force built around USS Lexington and USS Yorktown intercepted a Japanese force attempting to seize Port Moresby in New Guinea. It was the first battle in history in which the opposing surface ships never saw each other. All the fighting was done by aircraft.

Lexington sank. Yorktown was badly damaged. But the light carrier Shoho was sent to the bottom, the fleet carrier Shokaku was heavily damaged and required months of repair, and Zuikaku lost most of her air group. The invasion of Port Moresby was cancelled.

For the first time since the war began, a Japanese offensive had been stopped. Two of the six fleet carriers that had struck Pearl Harbor were no longer available for the next major operation. Sixteen days before the Coral Sea battle began, the psychological ground under Tokyo had already shifted. On the morning of April 18, 1942, sixteen Army B-25 Mitchell medium bombers under Lieutenant Colonel James Doolittle launched from the flight deck of USS Hornet about 650 miles from the Japanese home islands.

Medium bombers had never been launched from a carrier in combat. The eighty volunteer airmen knew they could not land back aboard. Their orders were to strike Tokyo and other cities, then continue west toward airfields in nationalist China. The physical damage was trivial.

A few dozen buildings burned. About fifty Japanese died. The Imperial Palace was deliberately untouched, but American bombs had fallen on the Japanese capital, and that fact could not be changed. Four army fighter groups were pulled back to defend the home islands, groups desperately needed in the South Pacific.

Inside the Naval General Staff, the political balance shifted. Yamamoto had been urging for months that the Combined Fleet sail east to force a decisive engagement with the American carriers before American industry could replace them. The army had opposed the plan as an unnecessary risk. After the Doolittle raid, the argument that American carriers could be tolerated in the Pacific collapsed.

Operation Midway was approved. The plan was elaborate. Yamamoto himself would sail with the main force aboard Yamato, the largest battleship ever built, along with the battleships Nagato and Mutsu, the light carrier Hosho, and their screen of cruisers and destroyers. Nagumo’s First Air Fleet, reduced to the four heavy carriers Akagi, Kaga, Soryu, and Hiryu, would strike ahead to destroy Midway’s defenses and lure the American carriers into a trap.

A diversionary attack on the Aleutian Islands was meant to pull part of the American fleet northward. The entire operation involved more than 200 ships and about 100,000 men, the greatest concentration of Japanese naval force ever put to sea, and it rested on a single assumption. Yamamoto believed the Americans did not know he was coming. He was wrong.

In a windowless basement office at the headquarters of the Fourteenth Naval District at Pearl Harbor, a team of American codebreakers was reading his messages. The office was known as Station Hypo. Its leader was Commander Joseph J. Rochefort, a thin, insomniac officer who worked in comfortable clothes and slippers because the concrete floor was cold.

His team had been working on the operational cipher of the Imperial Japanese Navy, which American analysts called JN-25B, long before Pearl Harbor. By the spring of 1942 they could read enough of the traffic to identify Japanese units, sailing dates, and general operating areas. The Japanese target for the next major operation appeared repeatedly under the code letters AF. Rochefort was convinced AF meant Midway.

Some officers in Washington disagreed. Lieutenant Jasper Holmes, an officer on Rochefort’s staff, suggested a test. The Midway garrison was instructed to send an unencrypted message stating that their water distillation plant had broken down. Two days later, intercepted Japanese naval intelligence reported that AF was short of fresh water.

The identity was confirmed. Admiral Chester Nimitz, commander in chief of the Pacific Fleet, now knew Yamamoto’s objective, his approximate timing, and the general composition of his forces. What Nimitz did not have was carriers. Enterprise and Hornet were available.

Lexington was lost. Yorktown had been so badly damaged in the Coral Sea that Japanese intelligence assumed she had sunk. Repair estimates ran to three months. Nimitz gave the Pearl Harbor shipyard seventy-two hours.

Welders and shipfitters worked around the clock to repair her flight deck, patch her damaged hull, and return her to sea. She sailed for Midway held together in places by emergency welds. Nimitz now had three carriers against Nagumo’s four. Nagumo did not know they existed.

On the morning of June 4, 1942, the four Japanese carriers sailed toward a trap no one in Tokyo believed existed. The sun rose over an empty ocean. The first Japanese strike went in against Midway itself. The Americans, forewarned, armed, and still invisible, were already turning into the wind to launch.

Around seven in the morning, Nagumo’s strike force returned from Midway reporting that the island’s defenses required a second attack. The returning aircraft were struck below to the hangar decks and rearmed. Their armor-piercing bombs and torpedoes were replaced with fragmentation and general-purpose bombs suitable for land targets. That work was at its peak when a scout plane from the heavy cruiser Tone finally reported an American task force to the northeast.

Nagumo now had to reverse course. The torpedoes were removed from the aircraft again. Bombs were unloaded and set aside. Ordnance began piling up on the hangar decks because there was no time to strike it down to the magazines below.

Meanwhile, wave after wave of American aircraft was approaching from Enterprise, Hornet, and Yorktown. The torpedo squadrons arrived first and were annihilated. Torpedo Squadron Eight from Hornet, under Lieutenant Commander John Waldron, attacked without fighter cover. All fifteen of its TBD Devastators were shot down.

Of the thirty men aboard, only one survived, Lieutenant George Gay, floating in the water on his seat cushion. Torpedo Squadron Six from Enterprise lost ten of fourteen aircraft. Torpedo Squadron Three from Yorktown lost ten of twelve. No American torpedo hit its target.

Many of the weapons that entered the water either ran erratically or failed to explode. That sacrifice, unintended and terrible, decided the battle. Every Japanese fighter had dropped to sea level to chase the torpedo bombers. No combat air patrol remained high above.

At about 10:20 in the morning, thirty-three Dauntless dive bombers from Enterprise under Lieutenant Commander Wade McClusky began to fall out of the sun. A communication error sent most of his aircraft against Kaga. Lieutenant Richard Best realized what was happening at the last moment, pulled out with his plane and two others, and attacked Akagi. Almost simultaneously, seventeen Dauntlesses from Yorktown under Lieutenant Commander Max Leslie fell on Soryu from the other side of the Japanese formation.

In roughly six minutes, three carriers of the Imperial Japanese Navy were destroyed. The bombs that were supposed to start controllable fires instead hit decks and hangars packed with fueled aircraft and unstowed ordnance. Kaga took at least four hits and burned out of control. Akagi took a single bomb that set off secondary explosions among the armed and fueled aircraft in her hangar.

Soryu took three hits and was abandoned within twenty minutes. Hiryu, left undamaged alone, launched two counterattacks that evening. Her aircraft found Yorktown and mortally wounded her. Late the same day, Dauntlesses from Enterprise found Hiryu and left her blazing.

All four carriers Nagumo had brought to Midway were sunk within twenty-four hours. Japan lost about 3,000 sailors and airmen and more than 240 aircraft. The United States lost Yorktown, the destroyer Hammann, about 150 aircraft, and 307 men. The four carriers destroyed at Midway had been the core of the First Air Fleet that struck Pearl Harbor.

In six minutes of dive bombing, the striking arm that began the war ceased to exist. The Imperial Japanese Navy tried to hide the scale of the defeat. Midway was announced to the Japanese people as a great victory. Wounded sailors returning to Japan were isolated in separate hospital wards and forbidden to contact their families.

Surviving officers were transferred to distant commands. Aboard the battleship Yamato, Admiral Yamamoto withdrew to his cabin and ordered the operation cancelled. The six months he had promised the naval staff two years earlier ended almost to the day. Two months later, on August 7, 1942, the First Marine Division under Major General Alexander Vandegrift landed on Guadalcanal in the Solomon Islands.

The objective was an unfinished Japanese airstrip. Renamed Henderson Field after a Marine pilot killed at Midway, it became the anchor of a six-month campaign that shattered the second great Japanese assumption of the war. Japanese commanders had planned to face Americans who would not stand and fight in close combat. Before dawn on August 21, Colonel Kiyonao Ichiki led about 900 men into a frontal attack across the Ilu River, mislabeled Tenaru on American maps.

Marine machine guns and 37mm cannon tore his force apart. About 800 Japanese soldiers died. Marine losses were about 150. Ichiki burned his regimental colors and died on the battlefield.

Larger attacks followed. Major General Kiyotake Kawaguchi’s 6,000-man brigade was defeated at Edson’s Ridge in September with the loss of more than half its strength. In late October, about 7,000 men under Lieutenant General Masao Maruyama attacked the American perimeter around Henderson Field and were repulsed with losses in the thousands. When Japan evacuated its forces from the island in February 1943, it had lost about 25,000 soldiers, most to starvation and disease after American aircraft and submarines cut their supply lines.

Japanese soldiers called Guadalcanal Starvation Island. Behind the battlefield, the assumption on which the entire Japanese war plan rested, that American industry could not respond in time, was collapsing on a scale no one in Tokyo had imagined. In 1944 alone, American factories produced 96,318 aircraft. That single year’s output exceeded Japan’s entire wartime aircraft production of 76,320 planes from 1941 to 1945.

During the war, the United States built twenty-four Essex-class carriers. Japan completed six carriers of all types. Henry Kaiser’s yards launched 2,710 Liberty ships. One of them, Robert E.

Peary, went from keel-laying to launch in four days, fifteen hours, and twenty-nine minutes. Japanese naval intelligence estimated the American navy’s strength at about 309,000 personnel in late 1943. The actual figure was 2. 37 million, almost eight times higher.

No amount of fighting spirit could close that gap. Japan had no pilot rotation system. The skilled aviators who had struck Pearl Harbor and Midway kept flying until they were killed, while the United States rotated experienced pilots home to train the next generation. By the Battle of the Philippine Sea in June 1944, American fighters were shooting down Japanese aircraft at a ratio approaching twelve to one.

American pilots called it the Great Marianas Turkey Shoot. There was one final chapter to Yamamoto’s story, and it closed the circle Midway had opened. On April 14, 1943, Station Hypo intercepted and decrypted a Japanese message detailing an inspection tour Yamamoto would make of forward bases in the Solomon Islands. The message revealed the type of his aircraft, his escorts, his route, and his exact arrival time.

Admiral Nimitz approved an interception. On the morning of April 18, exactly one year after the Doolittle raid that had proven his point about Tokyo’s weakness, sixteen P-38 Lightning fighters launched from Guadalcanal and ambushed his two Betty bombers over Bougainville. Yamamoto’s plane crashed into the jungle. His body was recovered the next day, still strapped upright in his seat.

The war continued for another two and a half years, and its final years traced Japan’s disintegration. American submarines strangled the merchant fleet carrying oil from the Dutch East Indies to Japanese refineries. By April 1945, oil imports to Japan had stopped entirely. The kamikaze attacks, formally organized in October 1944, were an explicit admission that Japan no longer had trained pilots for conventional air combat.

Sixty-seven Japanese cities burned under American bombing. The firebombing of Tokyo on the night of March 9-10, 1945, killed roughly 100,000 people in a single raid. On September 2, 1945, aboard the battleship USS Missouri, the Empire of Japan signed the instrument of surrender. The ship on which they signed had been built in a Brooklyn shipyard, run on American oil, and armed by American factories, the same industrial system through which Yamamoto had walked as a young officer more than two decades earlier.

After the surrender, the United States Strategic Bombing Survey sent about 1,100 investigators to Japan. They gathered records, interviewed surviving military and civilian leaders, and reconstructed the decisions that led to war. Their conclusion about the central failure was brief. The survey found that Japanese military leaders had not believed the United States capable of instilling a fighting spirit in its people.

That was the miscalculation. It was not a failure of intelligence in the narrow sense. The data about American shipyards, American oil, and American factories had been available in Tokyo. Yamamoto himself had delivered it, in warnings that were read, discussed, and then ignored.

The failure was in reading American character. Japanese planners believed a democracy of immigrants and assembly-line workers could not sustain a long war of sacrifice against a distant enemy. They believed a prosperous society was necessarily a weak one. They committed the resources of an empire to that belief.

Two thousand four hundred Americans died at Pearl Harbor. More than two million Japanese soldiers died in the war that followed. The Imperial Japanese Navy was eliminated. Sixty-seven Japanese cities lay in ruins, two of them struck by weapons no one in Tokyo or anywhere else had imagined in 1941.

Admiral Yamamoto had walked the streets of Detroit and stood in the oil fields of Texas. He saw what was coming. But his country, which listened to men who had seen none of it, went to war anyway.