The Hiroshima Men: The Quest to Build the Atomic Bomb, and the Fateful Decision to Use It

by Iain MacGregor

A vivid account of one of history’s most significant the approval, construction, and fateful decision to drop the atomic bomb—based on new research and interviews, timed to coincide with the 80th anniversary of the Hiroshima attack.

At 8:15 a.m. on August 6th, 1945, the Japanese port city of Hiroshima was struck by the world’s first atomic bomb. Built in the US by the top-secret Manhattan Project and delivered by a B-29 Superfortress, a revolutionary long-range bomber, the weapon destroyed large swaths of the city, instantly killing tens of thousands. The world would never be the same again.

The Hiroshima Men’s unique narrative recounts the decade-long journey towards this first atomic attack. It charts the race for nuclear technology before and during the Second World War, as the allies fought the axis powers in Europe, North Africa, China, and across the vastness of the Pacific, and is seen through the experiences of several key General Leslie Groves, leader of the Manhattan Project alongside Robert Oppenheimer; pioneering Army Air Force bomber pilot Colonel Paul Tibbetts II; the mayor of Hiroshima, Senkichi Awaya, who would die alongside over eighty-thousand of his fellow citizens; and Pulitzer Prize–winning novelist John Hersey, who travelled to post-war Japan to expose the devastation the bomb had inflicted upon the city, and in a historic New Yorker article, described in unflinching detail the dangers posed by its deadly after-effect, radiation poisoning.

This thrilling account takes the reader from the corridors of power in the White House and the Pentagon to the test sites of New Mexico; from the air war above Germany to the Potsdam Conference of Truman, Churchill, and Stalin to the savage reconquest of the Pacific to the deadly firebombing air raids across the Japanese islands. The Hiroshima Men also includes Japanese perspectives—a vital aspect often missing from Western narratives—to complete MacGregor’s nuanced, deeply human account of the bombing’s meaning and aftermath.

Genres: Nonfiction, History, World War II, Biography, Politics, Audiobook, War

448 pages, Hardcover

First published July 3, 2025

About the author

Iain MacGregor has been an editor and publisher of nonfiction for over twenty-five years. As a history student he visited the Baltic and the Soviet Union in the early 1980s and has been captivated by Soviet history ever since. He has published books on every aspect of the Second World War on the Eastern Front 1941-45 and has visited archives in Leningrad, Moscow and Volgograd. He is a Fellow of the Royal Historical Society and his writing has appeared in the Guardian, the Spectator and BBC History Magazine. He lives with his wife and two children in London.

Reviews

[Michael Schramm · Rating 4 out of 5]

My fourth book on the events shaping the development of the atomic bombs that were developed in Los Alamos, NM in that fateful period leading to the end of WW2 and a
worthy treatise on a highly emotionally charged subject.

What Iain MacGregor adds in “The Hiroshima Men” is a very human element, the pages replete with many stories of desperation and pathos as we learn of and 87-year-old survivor’s description of her experience in Hiroshima with the dropping of the initial atomic bomb. From there, the reader gains additional insights from deeply personal accounts by way of TIME-LIFE John Hersey, B-29 “Enola Gay” pilot Paul Tibbets, among others.

MacGregor did a fine job in presenting the angst and quandary presidents Roosevelt and Truman faced in green lighting the Manhattan Project. Also noteworthy is the elucidation of the struggles and campaigns leading up to the deployment of the two nuclear bombs, providing considerable insight into the massive B-29 incendiary bombing campaign of mainland Japan, as well as the hard fought, costly battles on Iwo Jima and Okinawa that exacted a huge toll in human lives.

[Faith · Rating 4 out of 5]

This book traces the development of nuclear weapons and their deployment in Hiroshima at the end of WWII. It is a straight forward account, without any deep analysis of the impact their actions had on the scientists, military personnel or politicians involved. There was a lot more about the war in the Pacific, generally, than I was expecting. I knew almost nothing about the battles in Iwo Jima and Okinawa. The most impactful parts of the book are the accounts of what the people in Hiroshima, and their descendants, endured. This book made me want to read “Hiroshima” by John Hersey.

I received a free copy of this book from the publisher.

[Andrew Higgins · Rating 5 out of 5]

This is an incredibly powerful and well researched exploration of the events that led up to and culminated in the dropping of the first atomic bomb on Hiroshima on 6 August 1945 - I read this book as a lead up to the 80th Anniversary of the defining event of modern history. MacGregor tells this story through the lives of and experiences of people who lived through this period and event - including a city mayor. a bomber pilot, an Army General and an award winning journalist John Hersey whose account of Hiroshima I first read in the States in High School and want to read again. Highly recommend in a period in history where similar potential events seem to be more on the horizon.

[Jeff · Rating 4 out of 5]

Among The More Complete Histories Of The Nuclear Bombing Of Japan. Clocking in at nearly 450 pages, with only about 10% of that bibliography - and hence the star deduction - this account really is one of the more complete accounts of the entire event I've yet come across in all my years both reading books generally and studying WWII in its various facets more specifically. It was also the last of three books about the bomb and/ or the use of it that I read over the few days of US Memorial Day Weekend 2025 or in the days immediately after, the other two being Evan Thomas' 2023 book Road To Surrender and Frank Close's June 2025 book Destroyer Of Worlds.

Specifically, in tracking exactly who it does - including several key US personnel involved with both war planning and the Manhattan Project itself, the pilot of the bomber that dropped the bomb on Hiroshima, the reporter who really opened America's eyes to the horrors of nuclear fallout, and even the Mayor of Hiroshima himself - this book really does give a complete all around picture of all aspects of the creation and use of the atomic bomb and the repercussions for both American leadership and Japanese civilians.

Reading almost like a Tom Clancy or perhaps Robert Ludlum war thriller at times, this text *also* manages to have the emotional heavy hitting of Hersey's original Hiroshima report, which it covers in nearly as much detail as Lesley MM Blume's 2020 book Fallout - which told the story of that report exclusively. Leaning more towards the American position that as horrific as this event was, it very likely saved lives - American, Japanese, and even Russian - this is one of those texts that largely doesn't speak of the efforts in both America and Japan by several key, yet not quite highly ranked enough, leaders to at least consider trying to end the war through dialogue (ala Evan Thomas' 2023 book Road To Surrender), but instead seeks to offer the reader a more complete understanding of the men who *were* making the decisions in these moments, from the President of the United States all the way to the commander of the airplane that actually dropped the bomb itself.

Ultimately a thorough yet sobering account, and with its release intentionally timed just barely a month before the 80th anniversary of the Hiroshima bombing, this really is one of the most complete books I've ever encountered on the topic, one that at least attempts to strive for a balance in understanding *all* involved in this event. Thus, all -American, Japanese, and everyone else interested in discussing the event with intelligence and facts - would do well to read this particular accounting.

Very much recommended.

[Robert Fiore · Rating 5 out of 5]

"As I’ve gathered from the doctors, it’s quite a serene way to depart from life."

— Colonel Leslie Groves, during a Senate Committee meeting in November 1945.

Following the devastation of the atomic bomb, the Senate committee convened to examine the implications of this unprecedented event.

While this book may conclude with those hearings, it opens with an exploration of the origins and developments leading up to that momentous day.

At the heart of this story lies fission, the scientific principle that made the atomic bomb possible.

I have delved into multiple works detailing the harrowing events of August 6 and 9, 1945. This book is another addition to my curated library of literature that addresses this critical chapter in history.

Uncover the intricate process behind the construction of the B-29 Superfortress, an aircraft that symbolized a massive investment of billions of dollars and months of engineering challenges. Explore the roles of pivotal figures such as Colonel Leslie R. Groves, the military leader of the Manhattan Project; Robert Oppenheimer, the scientific director known as the "father of the atomic bomb"; John Hersey, who later documented the aftermath; General Jimmy Doolittle, an iconic military strategist; Paul Tibbets, the pilot who dropped the first atomic bomb; and Senkichi Awaya, the mayor of Hiroshima during that fateful time. What transpired for each of them during and after those critical days in August 1945?

Journey through the fog of war to the battlegrounds of Iwo Jima, Okinawa, and Tokyo, where countless men and women fought valiantly and made the ultimate sacrifice. And, if you are prepared to confront the harsh realities, learn about the lives of the men, women, and children who inhabited Hiroshima — those who attended school, worked, played, and lived their ordinary lives on the morning of August 6.

I have intentionally left out many details, urging you to purchase the book to uncover the full story. Key topics like the Manhattan Project, the strategic operations at Wendover, Utah, and the classified initiatives of Project Alberta are just a fraction of what awaits within its pages. I wholeheartedly encourage you to invest in this compelling narrative.

[Dawn Michelle · Rating 5 out of 5]

I've read about 10 books this year about World War 2, with three of them focusing on the making/dropping/aftermath of the atomic bomb, and to be honest, I recommend them all. They tell the story from different angles/POV's and I learned new information in each read.

That is the case with this absolutely excellent book about that very subject. Excellently-written, expertly-researched, it does deep dives into some specifics I had never read before as well as telling some of the haunting stories from Japan, before/during/after the bombing.

Overall, tis was an absolutely fantastic read that I'd recommend to anyone; it is history we cannot afford to forget.

**A NOTE: I must say that I also highly recommend the audiobook for this book. Read by the magnificent Stephen McGann [Dr. Turner from "Call the Midwife"], he tells this story is such a way that just takes you fully into the story, and often brings you to tears as he relates the stories out of Japan. He does an excellent job here and I can only hope he does more audiobook work; I think I would listen to anything he narrates.

Thank you to NetGalley, Iain MacGregor, and Scribner for providing both the eBook and physical copy ARC's in exchange for an honest review.

[Martin Petersen · Rating 4 out of 5]

MacGregor tells the Hiroshima story through the eyes of four men: General Groves, Paul Tibbets, John Hersey, and the mayor of Hiroshima. For me the unique contribution to this story is the focus on Mayor Awaya and his family. For a more detailed account of the Manhatten Project, read The Making of the Atomic Bomb by Richard Rhodes. I also recommend Chris Wallace's Countdown 1945 that covers Tibbets in greater detail and tells the story of the 116 days before the bomb was dropped. I also recommend Downfall the End of the Imperial Japanese Empire by Richard Frank.

[Craig Beyers · Rating 5 out of 5]

This is an incredibly thorough book about the people involved in conceiving, developing, planning for, training, and dropping the two atomic bombs on Japan in World War II. The author describes the activities in the U.S. and Japan in the struggle to win the war in the Pacific and describes the attitudes and decisions of both American and Japanese military and governmental officials. The book documents a horrible result resulting, mostly, from economic conditions and Japanese arrogance about their superiority. Highly recommended.

[Eric · Rating 3 out of 5]

Sounded like a straight telling of stories of most of the key players who had a role in the bombing with a nuclear device of the Japanese cities of Hiroshima and Nagasaki. I learned in the afterward that Paul Tibbets' grandson became a pilot of a B-2 with the 309th and commanded that contemporary unit.

[John · Rating 5 out of 5]

The story of developing and using the first atomic bomb is told through the lives of four men; General Leslie Groves, leader of the Manhattan Project, Paul Tibbets, pilot of the Enola Gay, Senkichi Awaya, mayor of Hiroshima, and John Hershey, author of Hiroshima. The book also covers a lot of different campaigns of the Pacific War. Interesting throughout and well written

[Andy · Rating 5 out of 5]

Wow, this was a fantastic read. The author does an incredible job of humanizing the events in Hiroshima. The research is impeccable, but it's the personal stories that really make this book so moving and unforgettable. Highly recommend it to anyone wanting a more human look at the first atomic bomb.

[Andrew Alvis · Rating 5 out of 5]

Thoroughly researched with many sources cited, if you ever wanted a detailed dive into the minds of those involved in the events that took place on August 6th 1945, on both sides of the conflict, I cannot recommend a better book.

[Keith Barrett · Rating 4 out of 5]

About more than the bomb. About everything that went into the development of the bomb and it's delivery systems. The tragic results of using it, in comparison to the costs of not using it.

[Cline Gary · Rating 3 out of 5]

Fairly good book, mostly about the war in the South Pacific. Different vignettes about some key people.

[Joseph H · Rating 5 out of 5]

Outstanding read. Loved how the author presented the story from several key individuals both American and Japanese. Easy to read and the writing style was exactly to my liking.

[Richard Fowler · Rating 5 out of 5]

really enjoyed this. for someone who knows the story of Hiroshima sketchily, it filled in gaps, is very well written and provides great variety of perspectives. highly recommend

[Mark Green · Rating 3 out of 5]

Was a bit disappointed. There was a factual error early on (roar of jet engines???( which made me doubt the rest. Not much on the actual challenges of the Atomic Program either.

[Michael Brown · Rating 5 out of 5]

Excellent profiles of all the angles of the war leading up to and aftermath of Hiroshima bomb. Super insightful and an easy read. Great WWII history.

[Robin · Rating 5 out of 5]

Excellent review of the path to the use of atomic weapons in WWII. The use of 4 main characters helped me to connect all the disparate stories I’ve read or been told about that time.