NATO's next test will be measured not in percentages of gross domestic product but in its ability to defend allied territory, deter aggression and sustain military operations against a capable adversary. At the 2025 summit in The Hague, the allies pledged to invest five per cent of their economic output in defence and security by 2035. What matters most, however, is closing the gap between the agreed regional defence plans and the forces actually available.

This is becoming more important as the US and Europe redistribute their defence responsibilities. The European allies would need to expand their capabilities substantially before American contributions fall. That is the assessment of David M. Cattler, a senior fellow at the Center for European Policy Analysis (CEPA).

Key points:

• The alliance's next test will be measured not in percentages of GDP, but in whether it can defend its territory, deter aggression and sustain military operations against a capable adversary.
• At the 2025 summit in The Hague, the NATO allies committed to investing five per cent of GDP in defence and security by 2035.
• Europe has underinvested in its defence for decades.

Source: CEPA (English)