Iran and the NATO Summit

Alliance leaders now have additional pressing issues on their agenda.
June 23, 2025

The 2025 NATO summit was meant to be about transatlantic burden-sharing, new defense spending commitments from allies amid the war in Ukraine. It was also to be a critical opportunity to gauge the Trump administration’s dedication to the alliance and European security. These topics will still be front and center when leaders meet in The Hague this week. But the unfolding conflict with Iran is likely to exert a significant influence on the gathering and the policy debates to follow. 

First, leaders will want to hear directly from President Donald Trump regarding the American calculus in striking Iran’s nuclear facilities and his administration’s thinking on what may follow. This will include issues pertaining to the Israel-Iran conflict and potential spillovers. Some but not all allies may differ with Washington on military support for Israel and the prospect for negotiations with Tehran.

Second, the Israel-Iran conflict underscores the significance of challenges already on NATO’s agenda, with implications for an alliance that seeks expanded capabilities in key areas. Air and missile defense, already topping the agenda in light of developments in the Ukraine war, will now appear as absolute priorities, directly linked to the protection of population centers. Allies are also likely to give greater weight to counterterrorism as a NATO mission, given the historic propensity of Iran and its proxies to use terrorism as a tactic. Intelligence and domestic security, traditionally excluded from conventional measures of defense spending, are likely to be among the items captured as part of the more comprehensive approach to be adopted in The Hague.

Third, NATO allies will likely share perspectives on how Iran might respond over the next weeks and months. Tehran’s threat to close the Strait of Hormuz would have serious implications for energy supply and price. How will allies react? The burden-sharing logic driving debates on both sides of the Atlantic might argue for a joint NATO operation to safeguard shipping and energy infrastructure in an around the Persian Gulf. It would be surprising if this contingency, which would affect Asian and transatlantic interests, is not discussed in some fashion at the summit.

Allies with the keenest appreciation of the consequences of the Ukraine war and the Russian threat for their own security will want to keep the meeting tightly focused on deterrence and eastward defense. But the conflict with Iran will surely produce a set of additional themes and priorities looking south. The summit may usher in a world in which European and Canadian allies are compelled to spend more and do more. Questions of how to spend it and where to act will be less clear-cut than they seemed just a week ago.