Europe’s defence without the U.S.: What does the new cost report say?

Strategic Culture, Erkin Oncan, May 23, 2025

A US draw‑down would leave a large “defence gap” for NATO’s European members.

The London‑based International Institute for Strategic Studies (IISS) has published a report entitled “Defending Europe Without the United States: Costs and Consequences.”

Founded in 1958, the IISS examines global security, defence and geopolitical issues, and its reports are frequently cited by NATO, the United Nations and national defence ministries.

Authored by Ben Barry, Douglas Barrie, Henry Boyd, Nick Childs, Michael Gjerstad, James Hackett, Fenella McGerty, Ben Schreer and Tom Waldwyn, the report concludes that if the United States withdrew from NATO, European countries would need to allocate USD 1 trillion to defence over the next 25 years.

That would mean raising defence spending to 3 percent of GDP.

According to the scenario, roughly 50 percent of total expenditure would go to procuring military equipment (tanks, armoured vehicles, aircraft, ships, missiles, UAVs, etc.); 25 percent to developing intelligence assets, space forces and command‑and‑control systems; 20 percent to equipping, training and logistically supporting personnel; and 15 percent to investments in the defence industry and purchases from abroad.

These hefty sums are based on a scenario in which all 128,000 US troops and their equipment are fully withdrawn from Europe by 2027.

What’s in the report?

The 32‑page report divides the threats Europe faces into two main headings.

The first points to Russia’s military power, noting:

“Russia’s economy is on a war footing and its defence industry is running at full capacity. Even if the fighting in Ukraine stops, Russia could rebuild its forces against NATO‑Europe.”

The second major problem is the shifting focus of the United States:

“Europe can no longer rely on automatic US support. Former President Donald Trump’s rhetoric on NATO and Secretary of Defense Pete Hegseth’s 2025 remark that ‘Europe must now shoulder its own defence’ show that Washington’s attention has pivoted to the Pacific. European allies therefore must build capabilities that can deter Russian aggression without US backing.”

The core assumption

The report assumes a mid‑2025 cease‑fire in Ukraine, after which the US begins to withdraw from NATO and pull troops out of Europe………………………………………………………………………………………………………………………………………………………………………………………………………………………………https://strategic-culture.su/news/2025/05/23/europe-defence-without-us-what-does-new-cost-report-say/