Europe's Sovereignty Turn: Four Scenarios for Defense Autonomy

European defense spending has increased 83% since 2015 - the largest increase of any world region. All 32 NATO members are expected to meet the 2% GDP target (up from 7 in 2022). The EU has taken on common debt for defense for the first time. The ReArm Europe / Readiness 2030 framework commits 800B EUR. Germany plans $77B over five years - potentially the world's third-largest defense budget by 2030. Trump's "pay-to-play" NATO model has landed as a planning assumption, not a hypothetical. Nuclear deterrence was high on the Munich agenda. Our D/E/M/A framework assigns 40% to "Fortress Europe", 30% to Transatlantic Reaffirmation, 20% to Strategic Autonomy Stalled, 10% to European Defense Realignment. Confidence: 60%, L3.

Probability Scores

The Numbers: A Quiet Revolution

Metric	2022	2025	Trend
EU defense spending	288B EUR	381B EUR	+32%
European NATO spending	$477B	$563B	+18%
NATO 2% compliance	7 members	32 members	All
Germany defense budget rank	#7 globally	Projected #3	By 2030
EU common debt for defense	0	150B EUR	First ever

The Atlantic has described this as "a quiet revolution in how [the EU] exercises power." The EU taking on common debt for defense - decided in May 2025 - represents a fundamental shift. Previously, defense was strictly a national competence. The realization that even serious spending hikes in individual countries would vary widely given economic disparities forced this collective approach.

The Trump Catalyst

Reports in late March 2026 that the Trump administration was exploring a "pay-to-play" NATO model - where allies failing to spend 5% of GDP could be frozen out of Article 5 collective defense guarantees - landed in European capitals as a planning assumption, not a hypothetical.

Each new threat has moved the needle: not just in rhetoric, but in contracts signed, budgets passed, and procurement lists quietly rewritten to reduce dependence on American hardware. The most consequential shift is happening inside Germany's defense procurement office - contracts that would have gone to US suppliers two years ago are now being sourced from European or domestic alternatives where possible.

The Nuclear Question

At Munich Security Conference 2026, nuclear deterrence was high on the agenda. Several countries announced bilateral talks on the issue. The core challenge: to achieve a credible deterrent to Russia that is no longer - or at least less - dependent on US capabilities, European countries will have to work out their different strategic visions.

Two proposals have emerged: one relying entirely on conventional deterrence, another on extending French (and potentially British) nuclear guarantees. Both are insufficient on their own. A European deterrence strategy will need an integrated and holistic approach.

Four Scenarios for European Sovereignty

Capability Gaps: The ReArm Europe Targets

The ReArm Europe / Readiness 2030 framework identifies nine critical capability gaps:

Capability	Current Status	2030 Target
Air and missile defense	Fragmented, US-dependent	Integrated European shield
Strategic enablers	Limited (satellites, C2)	Autonomous space/cyber
Drones	Import-dependent	European production capacity
Maritime systems	National fleets	Interoperable EU naval force
Military mobility	Logistics gaps	EU-wide corridor by 2027
Ammunition stocks	Depleted (Ukraine aid)	Strategic reserves rebuilt

Base Rates: European Defense Integration

Precedent	Outcome	Implication
EU defense integration (pre-2022)	Decades of talk, limited action	Crisis required for movement
Post-crisis spending sustainability	Mixed - Cold War sustained, post-2008 rapid cuts	Political will key variable
NATO 2% target achievement	10+ years for most members	5% will be slower
PESCO projects	50+ initiated, few operational	Implementation challenge

The historical pattern suggests European defense integration moves slowly - until crisis forces acceleration. The 2022-2026 period represents the most rapid movement in decades. The question is whether this momentum can be sustained absent immediate threat.

D/E/M/A Uncertainty Decomposition

D (Data Quality: 0.85) - Defense spending data is reliable (NATO reports, national budgets). Capability assessments are public. However, procurement contract details and delivery timelines are less transparent.

E (Epistemic: 0.70) - Better data on defense industry capacity, political sustainability of spending, and nuclear sharing negotiations would narrow uncertainty. Key unknown: US 2028 election outcome.

M (Model: 0.65) - Long-horizon prediction (5 years). Models for European integration have historically underestimated both inertia (pre-crisis) and acceleration (post-crisis). Current acceleration may or may not sustain.

A (Aleatoric: 0.60) - Irreducible randomness includes: major terrorist attack in Europe, economic recession, leadership changes (Macron, Scholz), unexpected Russian collapse or escalation.

What to Watch

Resolution Tracking

Prediction	Deadline	Our Call	Outcome	Correct?
All NATO at 2%	2026	Yes (95%)	TBD	TBD
EU military mobility corridor	2027	Partially operational (60%)	TBD	TBD
Germany #3 defense budget	2030	Yes (70%)	TBD	TBD
European nuclear sharing framework	2030	Unlikely formal agreement (25%)	TBD	TBD