140 Days to Hiroshima

The Story of Japan's Last Chance to Avert Armageddon

David Dean Barrett

• Publisher: The History Press
• Year: 2020
• Print ISBN: 9780750995962
• eBook ISBN: 9780750996013
• Topic: History
• Subtopic: World War II
• Index: History

During the closing months of the Second World War, as America's strategic bombing campaign incinerated Japan's cities, two military giants were locked in a death embrace of cultural differences and diplomatic intransigence. The leaders of the United States called for the 'unconditional surrender' of the Japanese Empire while developing history's deadliest weapon and weighing an invasion that would have dwarfed D-Day. Their enemy responded with a last-ditch call for the suicidal resistance of every able-bodied man and woman in 'The Decisive Battle' for the homeland. But had Emperor Hirohito's generals miscalculated how far the Americans had come in developing the atomic bomb? How close did President Harry Truman come to ordering the invasion of Japan? Acclaimed historian David Dean Barrett recounts the secret strategy sessions, fierce debates, looming assassinations and planned invasions that resulted in history's first use of nuclear weapons in combat, and the ensuing chaos as the Japanese government struggled to respond to the reality of nuclear war.

1

TOKYO BURN JOB

More than 70,000 men in the 3^rd, 4^th, and 5^th Marine divisions invaded Iwo Jima on February 19, 1945. In anticipation of the most intense ground fighting of the war—what the U.S. knew would be a fiercely determined opposition—the assault was supported by 800 ships and 220,000 naval personnel.¹

Located midway between the American B-29 bomber bases in the Marianas and the main islands of Japan, the tiny speck of volcanic earth was invaluable amid the vast Pacific Ocean, its runways representing salvation for crippled B-29s returning from bombing missions. Taking the island and eliminating its enemy radar station also deprived the Japanese of an early warning system for attacks on the home islands and eradicated the risk of any further attacks by Japanese planes against Guam, Saipan, and Tinian as well.

In the thirty-six days of combat it took to wrest the eight-square-mile island from its 20,000-plus defenders, 19,217 Americans were wounded and a further 6,822 killed—853 men for every square mile. Japanese losses were nearly total.

The new air offensive from the Marianas—which began in late November 1944—was a huge logistical improvement over the India-China operations, but it remained ineffective. To take advantage of the newest, most sophisticated, and expensive heavy bomber in America’s arsenal—the B-29—the bombs were being dropped from over 25,000 feet during the day. The bombs were often miles off target, primarily due to the persistent existence of the jet stream and cloud cover over Japan.

Things quickly changed when, on January 20, 1945, a rising star in the United States Army Air Forces, thirty-eight-year-old Curtis LeMay, nicknamed “Old Iron Pants,” took control of the XXI Bomber Command headquartered at Harmon Field on Guam. A veteran of nearly two years of aerial combat with the Eighth Air Force in England, LeMay had helped develop the “combat box” formation used over Europe. The configuration protected heavy bombers against fighter attack by maximizing the defensive firepower of all the .50 caliber machine guns of the planes in the formation, while at the same time concentrating the bomb pattern on the target. Future Secretary of Defense Robert McNamara described LeMay as “the finest combat commander of any service I came across in the war.”

Sent to the Pacific to produce results, throughout February and into the first week of March LeMay and his staff worked on plans that radically altered the XXI’s bombing tactics. No longer would the B-29s bomb from high altitude. Instead they would fly at less than ten thousand feet, under the cover of darkness. The lower altitude reduced the amount of fuel required for missions while also easing the stress on the plane’s finicky R-3350 engines. And in an extreme effort to reduce all possible weight, all the B-29s’ .50 caliber machine guns were removed, except for the twin .50s in the tail of the plane. Less weight translated into bigger bomb loads.² To minimize the exposure of aircrews to flak and fighters, LeMay introduced a concept he called “compressibility,” the bombers “forming up and concentrating over the target in minimum time to overwhelm defenders.”³ LeMay, who had flown a number of missions in Europe, had wanted to lead this attack using the new tactics with his men, but he had been grounded for the sake of security after being briefed about the atomic bomb.⁴

The B-29s’ primary weapon would be the M69 incendiary bomblet. Nicknamed Tokyo Calling Cards, M69s were hexagonal steel cylinders three inches in diameter and twenty inches long, weighing 6.2 pounds. Each bomblet contained Napalm-B encased in cheesecloth as its incendiary filler. The improved version of napalm included newly added polystyrene and benzene, which yielded a longer-burning fire at temperatures up to 2,000 degrees Fahrenheit. Thirty-eight of the bomblets were enclosed in a finned E-46 aimable cluster. The cluster opened at a designated altitude, typically 2,000 feet, and would spread its munitions across a 500 feet by 2,500 feet swath. Each of the M69s had a three-foot-long cotton streamer, resembling the tail of a kite, to orient its fuse downward, control the velocity of descent, and spread the munitions as they dropped to the target. After hitting a building or the ground, the timing fuse burned for three to five seconds before detonating a white phosphorous charge. The explosion propelled flaming globs of napalm up to a hundred feet, instantly starting intense fires. A typical bombload for a B-29 included forty cluster bombs or 1,520 M69 bomblets.⁵

Tokyo, the first target for LeMay’s ten-day mini blitz, would be the recipient of half a million such bomblets.

MARCH 9–10, 1945

In the lead-up to the raid on Japan’s most populous city, 13,000 men on three Pacific islands toiled nearly non-stop for thirty-six hours to ready the fleet of planes for its mission. At 5:36 p.m. on March 9, 1945, the first B-29 crews started rolling down Guam’s runways and continued, one at a time, in fifty-second intervals.⁶ At the same time, planes began taking off from Saipan and Tinian.

After six hours of flight, at about 11:40 p.m., the lead elements of 325 B-29 Superfortresses from the 73^rd, 313^th, and 314^th Bombardment Wings approached the coast of Japan. The crewmen donned flak vests and helmets and strapped themselves into their seats as tightly as possible. Only the dim light of a crescent moon and the stars above brightened the dense blackness.

Spread out over more than two hundred miles,⁷ the planes looked like giant roller coaster hills horizontally staggered left and right of a center line and vertically in steps at altitudes from 5,000 to 7,900 feet.⁸ Short, blue flames burned from the two superchargers on the back side of each of the B-29s’ four engines.⁹ Ironically, crewmen from the 73^rd Bombardment Wing listening to Radio Tokyo on their flight to the city heard, among other selections, “Smoke Gets in Your Eyes,” “My Old Flame,” and “I Don’t Want to Set the World on Fire.”¹⁰

Just south of the Chiba peninsula, the great armada split in two. From there the 314^th flew parallel to the coastline of Tokyo Bay. The 73^rd and 313^th soared past the eastern side of the Chiba peninsula and then turned northwest.¹¹

At 12:07 a.m. on March 10, the lead pathfinders, sweeping in low and fast at nearly 300 miles an hour and at right angles to each other, unleashed their white phosphorous M47 bombs to mark the primary target. With superlative navigation, the crews managed to ignite a fiery cross on the ground to literally show “X” marks the spot. The part of downtown Tokyo chosen for the attack measured about three by four miles, and was located between the southwest corner of the city’s main rail station and the Sumida River. Despite the evacuation from cities of great numbers of Japanese, including children, a huge population of essential laborers remained. The target area “teemed with life: an estimated 750,000 workers crammed into the twelve square miles of low-income housing and family-operated factories. It may have been the most densely populated place on earth.”¹² As more pathfinders flew over the target and released their payload, searchlights pierced the night sky and succeeding planes quickly encountered both beams of light and anti-aircraft fire. One of the lead aircraft was hit almost immediately and plunged “like a ball of fire” into the ground at 12:16 a.m.¹³ With the target area now clearly marked, planes from the main group commenced dropping their E-46 clusters onto a swiftly growing fire. From the ground, Father Gustav Bruno Maria Bitter said the M69 bomblets reminded him of “a silver curtain falling, like the lametta, the silver tinsel that we hung from Christmas trees in Germany…And where these streamers…touch[ed] the earth, red fires would spring up.”¹⁴ Houses and buildings flared like the fuses of a firework as they were hit.¹⁵ Smoke rising from the city quickly infiltrated open bomb bays and crewmen picked up an uncharacteristic odor—the sickening, sweet smell of burning flesh.

The thick smoke also created the potential for midair collisions. In one such instance, two B-29s had begun their bomb runs at almost the same time, but at two different altitudes. As they converged on the city, the distance between them had become dangerously close. As the lower of the two planes was making final preparations, the co-pilot looked up and saw catastrophe in the making—a B-29 emerging from the smoke directly above them, its bomb bay doors already open. The co-pilot screamed the warning to the pilot, who immediately pushed the throttle forward and accelerated out from under the second B-29.

About an hour into the assault, the number of planes over the city had grown significantly, and the drone of their radial engines had become ever present.¹⁶ The scene greeting these airborne crews was beyond anything they could have imagined. A wall of flames stretched across the horizon; it looked like Hell on earth,¹⁷ a city engulfed in fire rising hundreds of feet into the air.

Powerful thermals belched from the ground, some as high as twenty thousand feet. One collided with a plane, suddenly pushing it upward a thousand feet. Just as abruptly, the plane hit an invisible wall of cold air, shoving it back down. The twin shocks produced a thunderous clap that reverberated throughout the cabin like two boards being slapped together.¹⁸ The violent shaking of the aircraft broke loose floorboards and threw the crew’s personal belongings and equipment everywhere and caused numerous cuts and bruises.¹⁹

Another black column of billowing smoke rose from the surface and hit the right wing of one of the B-29s, completely flipping the plane into a three-hundred-sixty-degree aileron roll, plunging it toward the burning city. Miraculously, the pilots managed to regain control seconds before the plane would have hit the ground.²⁰

Searchlights endlessly swept the sky looking for the massive bombers. Japanese crews manning the searchlights attempted to get multiple lights onto a single plane. When successful, the effect created what looked like an inverted cone above the plane. B-29s ...

Table of contents

• Cover
• Title
• Copyright
• Contents
• Author’s Note
• Prologue
• 1. Tokyo Burn Job
• 2. A Third Prime Minister in Less Than a Year
• 3. A New President Gets Up to Speed
• 4. Planning for the Invasion of Japan
• 5. Ketsu-Gō, “The Decisive Operation”
• 6. Potsdam Declaration, A Missed Opportunity
• 7. The Final Countdown Begins
• 8. Hiroshima
• 9. A Shift of Power, The First Imperial Intervention
• 10. The Second Imperial Intervention
• 11. A Failed Coup d’État and Surrender
• Epilogue: Traditionalists and Revisionists
• Map of Operation Downfall, The Proposed Invasion of Japan
• Acknowledgments
• Bibliography
• Notes
• About the Author