Applying the System Asset Pricing Model to WMD Capability Diffusion: Measuring the System Welfare Cost of Weapons of Mass Destruction Proliferation

each dollar of annual industry revenue from WMD-adjacent activity destroys $21.92 in expected system welfare

The paper estimates β_W = 21.92 (90% CI: 13.8–36.6) using the System Asset Pricing Model. Private payoff Π = 86.4B/yr; system welfare cost Π_C = 1,894B/yr. The system-adjusted payoff Π = −$1,807B/yr.

• Private payoff sources: nuclear fuel cycle (28.7B), dual-use defense exports (24.2B), chemical precursors (18.1B), biological equipment (9.8B), verification services ($5.6B)
• Welfare cost channels: direct detonation harm (798B), defense-spending diversion (500B), geopolitical externality (406B), environmental damage (150B), institutional failure ($40B)
• Ratio is not metaphorical: small private revenue rides on large probability-weighted system loss

WMD diffusion is a private-systemic tension game

The paper identifies four structural conditions: positive private payoff, system welfare cost exceeding private payoff, welfare cost structurally independent of payoff space, and an impossibility theorem binding the ratio.

• Bilateral transactions contain no price term for third-party strategic choices across borders and time
• Centrifuge sold as civilian hardware can complete a weapons pathway; DNA synthesizer can expand biological weapons capability
• Market clears because decisive cost is borne by excluded parties, not contracting firms

No market mechanism can push β_W below approximately 8.0

The Capability Diffusion Ceiling (Theorem IX) proves a structural floor under three axioms: Security Necessity, Knowledge Transfer Identity, and Proliferation Ratchet. Even optimal institutional design leaves an irreducible residual.

• A1: At least one state always retains incentive to preserve WMD-relevant capability
• A2: Once weapons-relevant knowledge is transferred, it remains weapons-relevant regardless of civilian label
• A3: Asymmetric capability advantage induces imitation, hedging, or breakout pressure
• Impossibility floor ≈ 8.0; residual welfare cost ≈ $690B/yr even under best-feasible design

Full nonproliferation compliance could reduce welfare cost by 80–91%

The cooperative baseline W₀ defines the security dividend under universal NPT, CWC, BWC compliance with effective verification. Residual costs remain because knowledge cannot be un-transferred.

• Direct harm residual: 240–600B/yr (from $798B)
• Opportunity cost residual: 150–300B/yr (from $500B)
• Geopolitical externality residual: 120–280B/yr (from $406B)
• Environmental and institutional residuals also compressed but not eliminated

Direct detonation harm dominates at $798B/yr expected cost

Probability-weighted expected damage from nuclear, biological, and chemical weapons use. Anchored in published nuclear exchange modeling (Toon et al., 2019; Xia et al., 2022) and catastrophic risk frameworks.

• 1% annual probability of nuclear exchange causing 250T damage yields 2.5T/yr from that scenario alone
• Multiple WMD modalities across probability distribution informed by expert elicitation and historical near-miss data
• Nuclear/biological/chemical attribution shares are authorial judgments, exposed to challenge

Defense-spending diversion costs $500B/yr in foregone welfare

WMD-attributable fraction of global military expenditure—nuclear weapons programs, ballistic missile defense, chemical/biological defense, counterproliferation intelligence—redirected from productive investment.

• Based on SIPRI (2024) military expenditure data and guns-versus-butter elasticities
• Each additional dollar of military spending reduces GDP growth by ~0.40–0.70 in foregone productive investment
• Counterfactual: spending that would not occur in cooperative baseline with effective WMD control

Geopolitical externality adds $406B/yr net of direct-detonation overlap

Crisis instability, arms races, and strategic competition driven by WMD capability diffusion. Overlap with Channel 1 trimmed to avoid double-counting.

• Stability-instability paradox: nuclear weapons deter large war but enable limited conflict
• Pakistan's asymmetric escalation posture couples conventional crises to nuclear risk
• RAND geopolitical risk assessments inform probability calibration

Environmental damage and institutional failure add $190B/yr

Production and testing environmental damage (150B) includes nuclear testing legacy, uranium mining waste, and chemical weapons destruction. Nonproliferation regime maintenance and failure costs (40B) cover IAEA, OPCW, and BWC budgets plus enforcement gaps.

• Environmental channel subject to scientific debate on nuclear winter severity (Robock et al., 2007 vs. Reisner et al., 2018)
• Institutional channel includes verification costs and costs of treaty evasion (e.g., North Korea, chemical weapons evasion)
• Both channels directionally robust but with wider uncertainty ranges

The $86.4B private payoff is concentrated in five tiers

Nuclear fuel cycle commerce (28.7B), defense-industrial dual-use exports (24.2B), chemical precursor trade (18.1B), biological equipment sales (9.8B), and verification/compliance services ($5.6B).

• Firms include URENCO, Rosatom, Orano, Lockheed Martin, BAE Systems, BASF, Dow, Thermo Fisher, Illumina
• Boundary excludes purely defensive military expenditure and broad dual-use sectors like semiconductors
• Payoff boundary choice is contestable; narrower boundary would raise β_W, broader would lower it

Direct harm and opportunity cost channels are well-anchored; environmental and institutional channels are more uncertain

The paper uses

• Nuclear exchange modeling, SIPRI data, and RAND assessments provide strong empirical grounding
• Biological tail probabilities are poorly measured; engineered pandemic probability estimates vary widely
• Five review triggers mandate recalibration: new nuclear-force counts, verified WMD use, synthetic biology screening changes, treaty reform, or reproducible challenge to attribution shares

Nonproliferation is one of the highest-return welfare investments available

The paper integrates five literatures—strategic studies, arms control, catastrophic risk, defense economics, dual-use governance—into a single metric. β_W = 21.92 reveals that underinvestment in nonproliferation is extreme.

• No prior framework achieved all four properties: dimensionless, comparable across domains, decomposable into channels, subject to impossibility theorem
• Even if β_W is overstated, downward-stress cases still leave the domain system-destructive
• Prediction: without stronger controls, biological share of direct-harm risk rises over next 15–25 years