Single-lever policy simulation · international

Defence spending (% GDP)

2.50%3.75%10-year projection

This report models the effect of raising defence spending from 2.50% to 3.75% — with every other government policy left unchanged — on the public finances, the NHS, Britain's standing abroad, housing and public opinion, projected over 10 years.

Bottom line

Eases International standing and Public satisfaction, but worsens Fiscal pressure, NHS staffing and Housing supply gap.

A single lever moved in isolation — which no real government does. Figures are modelled projections, not predictions. How the model works →

Direct effects

Fiscal pressure

strong pressure

Why: Each 0.25pp of GDP is roughly £7bn/year — defence spending is a top-5 budget pressure driver and scales linearly with this lever

Effect emerges within months

NHS staffing

moderate pressure

Why: Defence labour competition and budget envelope pressure both cascade into NHS recruitment — indirect but real

Effect develops over 1–2 years

International standing

moderate improvement

Why: NATO 2% floor is the political baseline; 2.5%+ signals serious commitment. UK positioning here shapes transatlantic and European security credibility

Effect develops over 1–2 years

Housing supply gap

mild pressure

Why: Construction labour pulled into defence infrastructure projects (bases, shipyards) reduces residential capacity in the short term

Effect develops over 1–2 years

GDP strength

negligible net effect

Why: Defence spending has modest industrial-base multiplier effects through BAE, Babcock, and the supply chain — positive but small GDP signal at the margin

Effect builds over 3–4 years

Knock-on effects

Reached indirectly, as the direct effects propagate through the system. Ordering reflects how the effect spreads, not a literal sequence in time.

Political riskmild
Hospital waitsmild
Rent pressuremild
House pricesmild
Social care staffingmild
Vacancy fill rateslight
Public satisfactionslight
Working-age populationslight
Model output — exact figures
Fiscal pressure6177 (+16)
NHS staffing7385 (+12)
International standing5060 (+10)
Housing supply gap7581 (+6)
Political risk6066 (+6)
Hospital waits6872 (+4)
Rent pressure7276 (+4)
House prices6569 (+4)
Social care staffing7073 (+3)
Vacancy fill rate5553 (-2)
Public satisfaction3840 (+2)
Working-age population5049 (-1)

Index points on a 0–100 scale. Lower is better for pressure metrics; higher is better for outcomes like GDP and satisfaction.

Defence spending (% GDP): 2.50% → 3.75% · Britain 2036