Europeanising NATO: Planning

The US strategic reorientation requires the European Allies to assume primary responsibility for their own security with an uncertain level of US contribution to any contingency. NATO’s established planning mechanisms—the Operations Planning Process and NATO Defence Planning Process—can provide a framework for managing this transition and, perhaps, enable the European Allies to influence US decisions.

The US should be held to its commitment to work through these processes as it draws down its posture in Europe. Meanwhile, the European Allies must provide the extra personnel required for the extensive planning effort and the additional, more diverse capabilities needed to fill a NATO Force Model that is likely to be depleted by US withdrawals.

The new US national security and defence strategies very clearly shift US priorities towards the western hemisphere and the Indo-Pacific, with direct implications for European security and the US contribution to NATO.[1] The US still identifies preserving the freedom and security of Europe as a vital national interest but also makes clear that Europe must take primary responsibility for its own defence. Noteworthy in the US National Defense Strategy is the statement that the US will seek to leverage NATO processes to incentivise Europeans.[2] The Alliance’s most important mechanisms for capability development and military planning are the Operations Planning Process (OPP) and the NATO Defence Planning Process (NDPP).

The OPP

The OPP is a standardised methodology for developing plans for potential military actions. It can be used for emerging real-world situations (crisis response planning) and for future anticipated threats (advance planning). The OPP comprises six phases and, with minor adjustments, can be applied at the strategic, operational and tactical levels of command. The degree of detail in planning varies: a concept of operations or contingency option provides a broad operational framework, outlining objectives and a generic concept, and requiring a significant amount of additional planning before implementation; a standing defence plan includes pre-assigned forces and can be executed immediately or with small adjustments. Advance planning requires regular revision as the security environment and the availability of capabilities and forces change.

The US will seek to leverage NATO processes to incentivise Europeans to take responsibility for their own defence.

The OPP’s advance planning process was used to generate the new regional defence plans that Allies endorsed at the Vilnius Summit in 2023.[3] These plans, based on potential real-world situations, are intended to improve NATO’s readiness and responsiveness to meet threats. They pre-assign specific forces to the defence of individual Allies.[4] Significantly, the Allies agreed that these plans should be the primary driver of their collective military requirements.

The NDPP

The NDPP is the main mechanism for translating collective military requirements into capability targets for individual Allies. Over a four-year cycle, it provides a coordinated, synchronised framework to harmonise national plans with collective efforts and deliver the capabilities and forces the Alliance needs to achieve its agreed Level of Ambition (LoA).[5]

The NDPP consists of five steps. Step one generates political guidance, defining the quantity and quality of forces and delivery timelines needed for Alliance operations. From this, in step two, Allied Command Operations and Allied Command Transformation identify minimum capability requirements. Steps one and two consider NATO’s collective requirements independently of which Allies might provide them. But in step three, these requirements are apportioned among individual Allies as capability targets, in accordance with the principles of fair burden-sharing and reasonable challenge. There is also an expectation that no Ally should provide more than half of each capability required, but given its dominance in defence, the US has sometimes been asked to provide most of, or even all, certain exquisite capabilities. The current package of capability targets was approved by defence ministers in June 2025.

In step four, Allies implement agreed capability targets (in reality, this step continues in parallel with other steps in the process). In step five, the NATO Strategic Commands and International Staff assess progress in implementing targets and identify shortfalls and associated operational risks.

The US Posture Shift

Both the regional defence plans and the NDPP capability targets that identify the forces required for their execution were, of course, approved prior to the publication of the new US strategies and likely exceed the current administration’s interpretation of fair burden sharing. US officials have indicated that they are closely monitoring capability delivery in the Alliance and are willing to coordinate any adjustments to their own contributions through established NATO planning processes.[6] Nonetheless, in May 2026, the US unilaterally announced that the four Brigade Combat Teams it has in Europe would be reduced to three and that a previously planned deployment of a long-range fires battalion would no longer proceed.[7]

It is simply not possible to assess with any confidence the availability of US assets to execute the Alliance’s regional defence plans.

It is not necessarily the case that the forces affected were allocated to the NATO Force Model (NFM)—the framework through which Allies declare national forces as being available to the Alliance—as US forces may be present in Europe for national reasons, or to implement bilateral agreements with their host nations.[8] However, SACEUR’s assessment that Allies would have to step up in providing naval vessels and crewed and uncrewed aircraft indicated that the US was withdrawing at least some units from the NFM.[9] A later announcement was more explicit, revealing the Pentagon’s intent to reduce fighter aircraft available to NATO by one-third, and strategic bombers by a half, as well as removing submarines, air-to-air refuelling aircraft, and armed reconnaissance drones (reductions that will inevitably also restrain the Alliance’s options for nuclear missions).[10] Furthermore, the US announced that it would undertake a six-month review of American posture and basing in Europe.[11] At this point, it is simply not possible to assess with any confidence the availability of US assets to execute the Alliance’s regional defence plans.  

NATO, however, is confident that these reductions—and by extension the broader Europeanisation of the Alliance—can be handled through its existing planning processes, without impacting the executability of the regional defence plans. This thinking, and the extent to which it has been proven so far, is laid out in a March 2025 comment published by two authors directly involved in NATO defence planning.[12] They argue that the US cannot be expected to bear the main burden of the defence of the Euro-Atlantic area and that the NDPP should ensure its share of capability targets is no longer disproportionate. They note that the ongoing NDPP cycle emphasises the delivery of capabilities required to implement the regional defence plans and indicate that the Alliance is broadly aware of the evolving US strategic posture. NATO defence planners, they state, have already begun to adjust capability targets to accommodate the transfer of responsibility. Nevertheless, they conclude that replacing key US capabilities will require a substantial increase in European and Canadian defence investment and that achieving this objective would take at least until the end of the decade.

Moving Forward

At the 2025 Hague Summit, NATO Allies agreed to invest 5% of GDP annually in defence, allocating 3.5% to developing military capabilities and up to 1.5% in defence- and security-related spending.[13] NATO, the European Allies and Canada must now identify how these resources may be used to replace capabilities that may no longer be provided by the US and establish realistic timelines for doing so. In planning terms, this will most likely require the use of the OPP to develop multiple contingency options, a selected subset of which can be elaborated and appended to the regional defence plans as a driver of collective military requirements for the NDPP. These options will need to reflect different levels of future US engagement.

Given the uncertainty of the US position, there is some urgency to complete this exercise, which will inevitably increase the workload across the NATO command structure. It is essential that the European Allies fill the lower command structure positions vacated by US officers due to the transfer of command of Allied Joint Force Commands Naples and Norfolk from the US to European nations. They should also consider temporarily assigning additional personnel to NATO planning teams to accelerate the revision process. The knowledge and experience they gain will also help, when they return home, in aligning national and NATO plans.

The European contribution to the NATO Force Model will need to be larger and more diverse.

The Alliance will also need to determine whether the necessary redistribution of capability targets can be handled through a limited out-of-cycle review or whether it is so fundamental that an entirely new NDPP cycle must be initiated. A new cycle would begin with revised political guidance and perhaps a reassessment of NATO’s LoA. This top-level direction would not only need to ensure the rapid execution of collective defence under Article 5, but also NATO’s capacity to protect its wider strategic interests in a landscape characterised by multiple regional rivalries, global economic dependencies, interconnected supply chains, and critical infrastructure vulnerabilities. As its own Strategic Concept recognises, the Alliance’s security interests are global in scope.[14] They also extend beyond traditional domains to include hybrid, cyber and space.

A further implication of the requirements to replace withdrawn US capabilities and be ready to implement multiple contingency options is that the European contribution to the NFM will need to be larger and more diverse. Allies possess significantly larger national force inventories than those currently assigned to NATO, and force generation processes have already been used to compensate for the reduced US contribution. For example, Allies have filled almost 90% of the air defence gap left by the reassignment of US assets.[15] This process will need to go much further, resulting in larger shares of national forces being governed by NATO requirements (or larger national forces overall, if Allies are not ready to accept this).

Conclusion

A Europeanised NATO will not need new planning mechanisms to succeed. The existing OPP and NDPP already provide a framework and a means to mitigate the impact of future US decisions. They provide transparency, predictability and coordination among Allies, while their consensus basis limits the potential for unilateral action. The Alliance thus already has effective, well-established procedures that can manage the current transition to European leadership—and the US has stated its intention to work through them.

The European Allies and Canada should do their best to insist that they do so and to ensure that politically driven US hostility towards its Allies during the transitional period does not undermine sensible planning (no revised planning system could withstand this).

Going through a structured planning process now will put the European Allies in a far better position to understand the prospects, limits, timelines and risks associated with their acceptance of a greater share of the conventional defence burden. They will thus be better placed to discuss with the US the consequences of the Pentagon’s decisions and, rather than being merely subject to them, may be able to influence them.

The challenge facing the European Allies and Canada is considerable, but manageable. In the introduction to the National Security Strategy, President Donald Trump writes that his administration is putting America First. The task for European Allies is to ensure that they do not become last.

Endnotes

[1] The White House, “National Security Strategy of the United States of America,” November 2025; Department of War, “2026 NDS. National Defense Strategy,” January 2026.

[2] Department of War, “2026 NDS,” 19.

[3] NATO, “Vilnius Summit Communiqué,” 11 July 2023, para 34.

[4] NATO, “Strengthening NATO’s eastern flank,” 17 June 2026.

[5] NATO, “NATO Defence Planning Process,” 16 April 2025.

[6] Department of War, “Remarks by Under Secretary of War for Policy Elbridge Colby at the NATO Defense Ministerial (As Prepared),” 12 February 2026.

[7] Department of War, “Statement Attributable to Assistant to the Secretary of War for Public Affairs (ATSW(PA)),” 19 May 2026; NATO, “Joint press conference with Admiral Giuseppe Cavo Dragone, Chair of the NATO Military Committee, General Alexus G. Grynkewich, Supreme Allied Commander Europe and Admiral Pierre Vandier, Supreme Allied Commander Transformation,” 19 May 2026.

[8] NATO, “NATO Force Model,” 2 April 2025.

[9] US European Command Public Affairs, “U.S. rightsizes NATO Force Model contributions,” 3 June 2026.

[10] Marcin Zaborowski, “Hollowing Out the Shield: US Strategic Defence Equipment Reductions and the Implications for European Security,” GLOBSEC, 23 June 2026.

[11] “Remarks by Secretary of War Pete Hegseth at the 2026 NATO Defense Ministerial in Brussels (As Delivered),” Global Security, 18 June 2026.

[12] Angus Lapsley and Pierre Vandier, “Why NATO’s Defence Planning Process will transform the Alliance for decades to come,” Atlantic Council, 31 March 2025.

[13] NATO, “The Hague Summit Declaration,” 25 June 2025.

[14] NATO, “NATO 2022 Strategic Concept,” June 2022.

[15] Discussions at NATO, June 2026.

Views expressed in ICDS publications are those of the author(s).