The North Atlantic Treaty Organization (NATO) will begin crucial negotiations in October to determine the forces and weapons systems allies will need to counter a potential Russian attack, as well as how to fund the new defence requirements. The alliance is preparing to redesign its military capabilities.

The talks will establish military capability targets for 2029, requiring each of NATO’s 32 member states to commit specific military forces and equipment.

The timeline is particularly significant because European officials have warned that Russia could be ready to attack a NATO member state by then.

At the same time, the administration of US President Donald Trump is considering a substantial reduction in America’s military presence in Europe. Such a decision could leave the alliance short not only of troops, but also of critical capabilities, including aerial refuelling aircraft, long-range missiles, and intelligence, surveillance and reconnaissance assets.

The forthcoming negotiations will test each country’s willingness to increase defence spending, whether Europe can meet a greater share of its defence needs without the United States, and whether NATO’s military plans should rely more heavily on emerging technologies such as robotics and artificial intelligence.

“It will be difficult,” a senior NATO diplomat told Politico, speaking anonymously because of the sensitivity of the issue. “Burden-sharing, the United States, how to reconcile the level of ambition with political priorities… It is a huge undertaking,” the diplomat added.

The process that will determine NATO’s military strength

Allies are expected to begin discussions in the coming days on the overall framework for the new targets, known as Political Guidance.

This is the first stage of a five-phase process called the NATO Defence Planning Process (NDPP). Through it, the alliance identifies the military capabilities it needs and then allocates specific commitments to member states.

French Admiral Pierre Vandier, NATO’s Supreme Allied Commander Transformation and the official leading planning for the future conduct of warfare, stressed that the aim this time was not simply to repeat an established procedure. “The ambition is for this cycle to be a process of transformation, rather than something ready-made and taken off the shelf,” he said.

Politico spoke to 15 current and former NATO officials and diplomats, identifying five key issues expected to shape the negotiations.

1. How many troops and weapons does the alliance really need?

The first and most important issue is determining NATO’s so-called “level of ambition” — the number of troops and military capabilities that allies will commit to providing.

Traditionally, member states have agreed that, in addition to the forces required for major military operations, the alliance should maintain 18 additional brigades, each comprising around 5,000 troops. These forces are intended for smaller-scale crisis-management missions outside NATO territory, such as those carried out in Afghanistan or Kosovo.

However, US pressure on European allies to assume greater responsibility for their own security, under the approach known as “NATO 3.0”, could lead to these requirements being reconsidered. A substantial reduction or even the complete removal of provisions for such smaller-scale military operations could be on the table.

At the same time, allies will consider whether the defence-planning process itself should be accelerated to keep pace with the exceptionally rapid rate of technological development on the battlefield. Artificial intelligence and ground-based robotic systems are already changing the nature of military operations, making faster adaptation of defence plans necessary.

Another issue will be how conventional military forces, such as infantry units and combat aircraft, can support nuclear-armed countries, including the United Kingdom and the United States.

Nassima Barrois, NATO’s director of nuclear policy, stressed that conventional military support capabilities were an integral part of the defence-planning process. “Conventional support capabilities are very much part of the NDPP process. This is one of the key messages we are emphasising ahead of the upcoming negotiations,” she said.

2. How will NATO fill the gap if the US pulls back?

The possibility of a reduced US military presence in Europe is one of the biggest sources of uncertainty.

The Pentagon is expected to complete its review of the deployment of US forces across Europe in December, just as NATO’s negotiations are under way.

Earlier this year, Washington had already withdrawn military assets from the pool of forces available to the alliance, including strategic bombers, fighter aircraft, drones, submarines and warships.

The forthcoming US review is causing concern among European allies because it could lead to further withdrawals of critical assets, such as heavy transport aircraft.

The fact that the review’s findings are expected midway through the negotiations could also delay the process.

Washington’s efforts to scale back its military presence in Europe will force allies to find ways to replace American capabilities. This will open a difficult debate over the fair distribution of financial and military burdens at a time when national budgets are under increasing pressure.

Camille Grand, head of the European aerospace, security and defence industries association ASD and a former senior NATO official, described the change. “Until recently, the whole NATO process worked like this: you calculated what the alliance needed and, when you found that you did not have everything, the United States filled the gaps,” he said, adding: “That is no longer the case.”

One proposal under consideration is to abandon strict requirements for specific weapons systems and replace them with operational objectives. For example, rather than requiring a country to possess a particular number of missiles, it could be tasked with neutralising Russian command centres.

This would give European allies greater flexibility, particularly those without access to US weapons systems such as Tomahawk cruise missiles.

Fabrice Pothier, a former NATO director of policy planning and current chief executive of the consultancy Rasmussen Global, believes alternatives are available. “We do not need thousands of Tomahawks. But we can have thousands of cheaper, low-cost alternatives,” he argued.

3. Geographic disagreements: Russia is not everyone’s only concern

NATO’s growing focus on the Russian threat could trigger fresh disagreements among member states, as some believe other serious security challenges also need attention.

Officially, the alliance adopts a “360-degree” security approach, under which it must address threats from every geographical direction. In practice, however, since Russia’s full-scale invasion of Ukraine in 2022, NATO’s focus has shifted significantly towards eastern Europe.

Over the past year, attention has also increasingly turned to the north, with the creation of a mission in the Arctic, largely in response to pressure from Donald Trump over Greenland.

Some allies, however, want greater attention paid to NATO’s southern and south-eastern flanks. Their concerns include the presence of Russian mercenaries in Libya, the potential weaponisation of migration flows, increased submarine activity, and drone attacks on ships in the Black Sea.

These differing priorities could complicate the allocation of military forces and financial resources.

“There is too much emphasis on the north,” one NATO diplomat said. “We need to redefine our priorities,” the diplomat added.

4. More drones or more tanks? The crucial question

One of the most important military dilemmas concerns the balance between emerging technologies and conventional weapons systems.

The war in Ukraine has demonstrated the decisive role of drones and autonomous systems, which are being used on a massive scale on the battlefield.

NATO must now decide whether to prioritise the development and procurement of more drones or continue investing at the same intensity in conventional equipment such as tanks and artillery.

Most member states have already drawn up plans to increase their use of unmanned systems. The United Kingdom announced this year that it would create a “hybrid fleet” relying heavily on autonomous assets, including Type 93 uncrewed underwater vehicles.

France has earmarked around €8.4 billion for drones and loitering munitions, while Germany plans to establish its first specialised unmanned-systems regiment over the coming year.

This shift is driven not only by technological advances but also by the demographic challenges facing Europe.

Difficulties recruiting new personnel into European armed forces are increasing the need to deploy autonomous systems. As Camille Grand explained: “One of the reasons pushing everyone towards more unmanned systems is that we have ageing societies. We have a manpower problem.”

At the same time, countries must find a way to keep pace with Russian technological advances without exhausting their national defence budgets.

Admiral Pierre Vandier said Russia produces nine million drones a year, a figure that, in his view, demands a “fairly radical effort” from the alliance. One solution he proposed was adopting a model of regular upgrades to military equipment, similar to a subscription service. Such a system would allow weapons systems to be continuously updated, reducing the risk of their becoming obsolete within a short period.

5. Lessons from Ukraine: What NATO should adopt — and what it should avoid

The fifth major issue concerns the lessons the alliance can draw from the war in Ukraine.

Most member states recognise that Ukraine makes a substantial contribution to European security, with a large military force possessing extensive real-world combat experience. It has also achieved rapid technological advances in critical areas, including aerial, maritime and ground-based drones, air-defence systems and missiles.

Particular importance is also attached to the advanced Delta battlefield management system, which Ukrainian forces use to collect and exploit operational intelligence.

These capabilities have led some member states to call for closer military and industrial cooperation with Kyiv. Other allies, however, warn that the lessons of the war in Ukraine cannot simply be transferred wholesale to NATO’s military planning.

This is because the alliance bases its military doctrine on a different approach: rapid manoeuvre operations, air superiority and precision strikes at long range.

By contrast, the war in Ukraine has largely taken the form of a prolonged war of attrition, characterised by extensive drone use and a continuous contest between offensive and defensive systems.

NATO’s top military commander, US General Alexus Grynkewich, addressed the issue during an appearance at the European Parliament earlier in October. “There are enormous lessons from this conflict that we need to draw on,” he said. However, he was quick to clarify that the alliance’s aim was not to copy the model of warfare used in Ukraine. “We do not want to fight this kind of war,” he stressed.