Dan Carlin’s Hardcore History: Addendum

Episode 34: Atomic Accountability
Date: November 28, 2025
Host: Dan Carlin
Guest: Dr. Alex Wellerstein, historian and author of The Most Awful Responsibility: Truman and the Secret Struggle for Control of the Atomic Age

Episode Overview

This episode features Dan Carlin in conversation with Dr. Alex Wellerstein, an authority on nuclear weapons history, discussing Wellerstein’s new book about President Harry Truman and the atomic bomb. The main theme explores the complex reality behind Truman’s decision-making at the end of WWII, challenging prevailing narratives about presidential control, moral responsibility, and the lasting impact of personal agency on nuclear policy.

Key Discussion Points and Insights

1. Why Return to Nuclear Weapons History?

• Dan Carlin explains his frequent revisiting of nuclear weapon subjects, defending it as under-discussed given its world-altering stakes (00:08).
  • Quote: “We don’t think enough about that…we should be talking about this much, much, much, much, much more than we do.” — Dan Carlin (00:31)
• He introduces Dr. Wellerstein and his book, noting its potential to upend decades of assumed knowledge about Truman and atomic decision-making (01:38–08:10).

2. Truman’s Unexpected Inheritance and the Myth of Command

• FDR’s late death left Truman uninformed about the Manhattan Project; he only learned about the bomb after assuming the presidency (04:29–06:26).
• Carlin and Wellerstein dispel the myth that Truman meticulously ordered atomic strikes with full awareness, revealing operational momentum had started before Truman was even briefed (06:26–08:08).
• Quote (on Truman): “Imagine being the person who ordered that. How do you sleep at night?...when you three-dimensionalize it, you realize there’s more to this story.” — Dan Carlin (07:16)

3. Truman’s Own Words: The Most Terrible Decision

• Carlin reads from Truman’s statements about the bomb, capturing his horror and personal struggle (09:19–10:42).
  • Quote: “It is a terrible thing to order the use of something that is so terribly destructive...for the wholesale slaughter of human beings.” — Harry Truman (as read by Carlin, 09:37)

4. Wellerstein’s Thesis: Truman’s Limited Understanding

• Wellerstein traces how Truman was not the “decider” in the modern sense—he never issued a formal order, but let existing military plans proceed (13:15–17:08).
  • Quote: “Historians have known for a while...that Truman didn’t decide to use the bomb...He was not asked, he did not order. This was done by other people.” — Alex Wellerstein (15:04)
• Central paradox: Truman seems to have believed Hiroshima was a legitimate military target, not a civilian city (13:15–18:17).

5. The Decentralized Decision Process of WWII

• Discussion of military autonomy in bombing choices (firebombing vs. atomic); presidential input was minimal for most strategic bombing (18:17–21:36).
• The atomic bomb’s “specialness” begins to be recognized, with debates over who should control its use (18:17–21:36).

6. Truman as Everyman: Reluctant President

• The episode highlights Truman’s “regular guy” reputation, thrust into unprecedented moral territory (22:59–26:59).
  • Quote: “He is, as you say, this sort of almost everyman figure…you have somebody later, like Eisenhower, who’s much more military guy…and Truman is just not.” — Wellerstein (24:13)
• Truman was not a Cold Warrior at first; he genuinely hoped for Soviet–US cooperation postwar (26:59–28:04).

7. Generational Challenge: 19th-Century Men Meet Nuclear Physics

• Truman’s struggle with understanding bomb technology is compared to modern politicians dealing with AI (26:59–28:04).
  • Quote: “It reminds me of legislators in Congress today trying to handle artificial intelligence.” — Carlin (27:09)

8. Morality Amidst Atrocity: Firebombing and Public Opinion

• The mass firebombing of Japan created a moral gray zone; using the atomic bomb was viewed as a continuation, not a gross escalation, by many at the time (31:44–38:41).
• Public support for bomb use was robust, with a majority in favor even after the war (37:13).
  • Quote: “Only 4.5%...believed the atomic bombs ought not to have been used at all.” — Carlin, citing Fortune poll (37:13)

9. Kyoto Debate and Truman’s Misunderstanding

• The crucial misunderstanding: Truman’s focus on removing Kyoto from the target list (due to its cultural significance), and his impression he’d forbidden bombing cities, not realizing Hiroshima was a city (42:55–49:52).
• Decisions made in ambiguous briefings led to Truman believing he’d authorized attack only on “purely military” targets (47:02).
  • Quote: “My argument is he actually thought that he knew more than he did about what was happening.” — Wellerstein (15:40)

10. Aftermath: Realization, Moral Trauma, and Policy Change

• Truman only learned the true civilian devastation after the Hiroshima bombing and reportedly suffered great anxiety (50:46–55:16).
• He halted further atomic bombings after Nagasaki, even as conventional firebombings continued (55:16–57:16).
  • Quote: “His whole goal is to never use nuclear weapons again.” — Wellerstein (60:00)
• The “presidential monopoly” on nuclear weapons use was established—primarily to prevent their use, contrary to modern assumptions (59:12–61:27).

11. Legacy: Nuclear Taboo and the Fate of the World

• The episode draws a direct line from Truman’s centralized control to the nuclear taboo that has prevented further use, even in crises such as the Cuban Missile Crisis (61:33–68:57).
• Speculation that had military authority been greater, nuclear weapons might have been used repeatedly during the Cold War (67:36–70:10).
  • Quote: “The irony of Harry Truman…I think, is that he’s the only president who presided over the use of nuclear weapons in war. He may be one of the main reasons they don’t get used again.” — Wellerstein (72:00)

12. Lessons for Today and the Problem of Individual Agency

• Wellerstein warns against overreliance on systems and strategies; the worldview of the individual with their “finger on the button” often matters most (73:45–76:40).
  • Quote: “If the system is set up in such a way that ultimately the position of the one person at the top is the opinion that everybody else will probably bend themselves around, then that person really matters.” — Wellerstein (75:45)
• Dangers remain: in the US, Russia, China, North Korea—a “single person…may be our firewall protecting us from some sort of nuclear Armageddon” (76:40).

Notable Quotes & Memorable Moments

| Timestamp | Speaker | Quote | |-----------|---------|-------| | 00:31 | Carlin | “We don’t think enough about that. I mean, I don’t even think that’s arguable.” | | 09:37 | Truman (read by Carlin) | “The atomic bomb is the most terrible bomb in the history of the world…Its use was the most terrible decision a man ever had to make.” | | 15:40 | Wellerstein | “My argument is he actually thought that he knew more than he did about what was happening.” | | 24:13 | Wellerstein | “[Truman] is, as you say, this sort of almost everyman figure… and in a way, it’s completely correct.” | | 37:13 | Carlin | “Only 4.5%…believed the atomic bombs ought not to have been used at all.” | | 60:00 | Wellerstein | “His whole goal is to never use nuclear weapons again.” | | 72:00 | Wellerstein | “He may be one of the main reasons they don’t get used again.” | | 75:45 | Wellerstein | “If the system is set up in such a way that ultimately the position of the one person at the top is the opinion that everybody else will probably bend themselves around, then that person really matters.” |

Important Timestamps (Key Segments)

• 00:00–08:10 — Carlin's intro: why focus on nuclear weapons?
• 09:19–13:15 — Launch of the interview; reading Truman’s “most terrible decision” quote
• 13:15–18:17 — Wellerstein on Truman’s mistaken understanding and military autonomy
• 18:17–22:59 — Discussion of how WWII command structure shaped nuclear striking policies
• 26:59–31:44 — The generational/technological disconnect: 19th-century leaders and atomic age weapons
• 37:13–41:52 — Public opinion, polls, and the limits of presidential/elite moral qualms
• 42:55–49:52 — The Kyoto incident and the misunderstandings that shaped history
• 55:16–61:27 — Aftermath: Truman’s realization, firebombings, and policy centralization
• 61:33–68:57 — How postwar nuclear policy evolved, its impact on Cold War flashpoints
• 72:00–78:18 — Lessons for today; the critical role of individual agency and the ongoing nuclear threat

Final Thoughts & Lessons

• The decision to use nuclear weapons at the end of WWII was shaped not by clear-cut command or deliberate evil, but by evolving systems, bureaucratic inertia, urgent wartime momentum, and (crucially) the individual misunderstandings and values of Harry Truman.
• Truman, thrust into decision amid chaos, believed he was acting with greater moral restraint than in reality; this misunderstanding, and his horror at what followed, led to his determination to prevent future presidents from being similarly uninformed or powerless.
• Centralizing authority over these weapons in the president’s hands was originally meant as a check, not an enabler, and has shaped global nuclear policy ever since.
• The enduring lesson: the fate of humanity can hinge on the character, understanding, or even the misconceptions of individual leaders—relevant now more than ever as nuclear arsenals remain at the fingertips of a select few worldwide.

Further Reading

• Dr. Alex Wellerstein — The Most Awful Responsibility: Truman and the Secret Struggle for Control of the Atomic Age
• Related books mentioned: Daniel Ellsberg’s The Doomsday Machine

“If people find the claims I make…to be hard to believe, please read the book. I fully acknowledge that these are big claims and require evidence.”
— Alex Wellerstein (77:13)