I attended a lecture on the institutional landscape of nuclear non-proliferation and disarmament this week. My rough notes are below.
How can we reduce the danger posed by nuclear weapons?
Discussion prompts:
- Do you see nuclear weapons as a danger?
Student views:
- [L: Yes, nuclear weapons are a danger and the relinquishment of nuclear weapons may also be a danger.]
- A2: Yes, and can be seen as deterrent.
- A3: Yes, a danger, not a deterrent.
Perspectives/focus areas
- Humanitarian view: Focus on annihilation and speed of destruction.
- Deterrence view: Current conflicts (e.g. Ukraine) highlight nuclear threats.
- Political tool: Nuclear weapons also act as leverage.
Example: An Ohio-class U.S. submarine carries enough firepower to destroy a country. France could theoretically be obliterated in under 80 minutes.
What it takes to build a nuclear bomb
Three key elements
-
Technology
- Scientific knowledge is widespread, but weaponization requires decades of engineering.
- E.g. mastering plutonium-239 alloys with gallium.
-
Economy
- Weapons programs require major financial investment.
-
Politics
- Political will determines whether or not to proceed.
- Some view tech as driving policy, but nuclear development is heavily politicized.
Institutional leverage
- Political pressure, economic sanctions, and material restrictions can inhibit proliferation.
Example:
- Nuclear Suppliers Group (NSG) – Controls transfer of sensitive tech and materials.
- Fissile material control – Without enriched uranium or plutonium, a bomb is impossible.
Should we care about nuclear danger?
- Debate: Did the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) reduce risk, or merely reflect national preferences?
- Nuclear testing until the 1990s made danger visible; that visibility has faded.
- Public lacks understanding; many fear “radioactive stuff” but know little of real effects.
Why are you interested in this?
To the lecturer, Hiroshima is a reason. Remembering and understanding the impact of nuclear weapons.
[L: For me, it was to help figure out how I feel about nuclear armament and disarmament, because my feelings on weapons in general have shifted since the full-scale invasion of Ukraine. Before, I would have never considered working on weapons of any kind. Less weapons in the world seemed like a mostly worthy goal. Now, I think I'd have much fewer qualms working on weapon components. Before, I'd have said nuclear disarmament should always be the goal. Now, I question what good that did to Ukraine to give up their arsenal. But these are all just instinctive reactions at this point, not informed opinions. I am hoping learning more about the topic of nuclear weapons, disarmament, non-proliferation, etc., will help me form an opinion that isn't based on a kneejerk reaction. This does also mean that I'm coming into this course with an inherent bias, and I'll have to be mindful of that.]Hiroshima
- 15 kiloton bomb – one of the smallest deployed.
- New tactical weapons are ~5kt.
- Beirut explosion (2020): ~1kt – useful comparison.
A 5kt bomb could devastate Uppsala’s city center.
Fallout depends on detonation altitude.
- Hiroshima had an airburst → minimal long-term contamination.
- Ground bursts (e.g. at Bikini Atoll) → persistent fallout.
Why build tactical nuclear weapons?
- Designed to match adversary capabilities (e.g. Russia’s “escalate to deescalate” doctrine).
- U.S. added tactical nukes (~5kt) to fill gap between conventional forces and strategic weapons (~200–475kt).
- Fallout varies: higher-altitude explosions reduce contamination.
- Tactical nukes offer flexible deterrence, but raise escalation risks.
Do political decisions matter?
Yes – politics can and has shaped the nuclear landscape.
Example
1958–1959 testing moratorium
- Proposed by Eisenhower, accepted by Khrushchev.
- Led to the Partial Test Ban Treaty (1963).
Communication and global governance
- Globalization allows greater coordination.
- Political choices should matter, but institutional progress is difficult.
Upcoming deadline
- New START Treaty (U.S. – Russia) expires in 2026 – last strategic bilateral treaty.
Mayors for peace
- Originated in Hiroshima.
- Grassroots disarmament effort.
- Over 8,700 cities have declared themselves “nuclear-free.”
- Any mayor can sign a declaration to join.
Nuclear institutions: joining vs withdrawing
Benefits of joining
- Access to civil nuclear tech
- Economic cooperation
- Security guarantees
Costs of joining
- No domestic deterrent
- Sovereignty limitations
- Status differentials
Benefits of withdrawal
- Increased sovereignty
- Ability to develop deterrent
Costs of withdrawal
- Reduced cooperation
- Security risks (e.g. arms races)
- Diplomatic isolation
The nuclear regime – dimensions
1. Material vs political
Material:
- Access to fissile materials
- Explosive and delivery system tests
- Knowledge transfer
- Technological components
Political:
- Weapons program decisions
- Deterrence strategies
- Superpower balance
- Economic-military calculations
2. Horizontal vs vertical proliferation
- Horizontal: Spread to new countries (e.g. Iran, North Korea).
- Vertical: Arsenal growth and modernization within nuclear states.
U.S. 2018 Nuclear Posture Review = Vertical proliferation (tactical nukes reintroduced).
Treaty examples
NPT (Non-Proliferation Treaty)
- Negotiated 1965–1968; entered into force 1970.
- 190 parties; legally binding.
Three pillars
- Non-proliferation
- Disarmament (Article VI – unfulfilled)
- Peaceful use of nuclear energy
IAEA safeguards**
Safeguards such as allowing IAEA to come to a member country’s nuclear facilities (e.g., power plants) once a month to check that nuclear activities are non-military. This is done once a month and built into the NPT.
Unequal system:
- “Nuclear weapon states” = those that tested nuclear bombs before Jan 1, 1967.
- Privileges baked into the treaty (e.g. P5). TPNW (below) aims to counter this asymmetry.
TPNW (Treaty on the Prohibition of Nuclear Weapons)
- Negotiated in 2017.
- Legally binding, but lacks robust verification.
- Promotes equal status for all states.
- Civil nuclear energy permitted.
- Critics point to self-reporting and enforcement weaknesses.
CTBT (Comprehensive Nuclear Test Ban Treaty)
- Negotiated 1994–96; not yet in force.
- Signed by U.S. but not ratified.
- North Korea (DPRK) is a required Annex 2 state, acting as a blocker.
- Is dead in the water.
CTBTO runs the International Monitoring System (IMS):
- Seismic, radiological, infrasound, hydroacoustic stations worldwide.
- Detected North Korea’s 2006 test.
[L: If this treaty is dead in the water and will never enter into force, who is funding IMS and is funding under threat?]Technology is in place, but treaty awaits political ratification.
New START Treaty
- Bilateral (U.S. – Russia), signed 2009, in force 2011.
- Caps:
- 1,550 deployed nuclear warheads
- 700 deployed ICBMs
- 800 launchers (deployed + non-deployed)
Inspection mechanisms
- Detectors for neutron fluxes + obscuring blankets verify warheads without revealing design.
Limitations
- Tactical nuclear weapons not included.
- Russia suspended participation in 2023.
Ongoing challenges
1. Verifiable definitions
- What constitutes a nuclear weapon?
- Effects-based criteria are limited. Only a detonation proves function — which we want to avoid.
2. Loopholes
- Legal texts often vague by design.
- Example: NPT doesn’t regulate naval reactors → AUKUS implications.
3. Verification
- Balancing transparency vs secrecy.
- TPNW lacks rigorous mechanisms — a major barrier to effectiveness.
External challenges
- Geopolitical context can undermine institutions.
- Example: War in Ukraine has sparked debate in South Korea and Japan about nuclear deterrence.
Looking ahead
Following lectures will include ethics and responsibility of scientists in the nuclear realm and the design of nuclear weapons/nuclear physics.