Just a few years ago, it would have seemed unthinkable: voices calling for increased defence spending within NATO are growing louder. The proposed spending target is 5 percent of each member state’s GDP—more than double the long-standing 2 percent benchmark.

From 24 to 26 June 2025, leaders will gather in The Hague for the next NATO summit, a meeting that could mark a historic turning point. Discussions about increasing defence spending have been ongoing for some time, kickstarted by the election of Donald Trump. Over the past months, the debate has accelerated at a rapid and alarming pace. In recent days, it appears they have passed the tipping point: NATO is now heading decisively towards a new era.

Mark Rutte, the Secretary General of NATO, stated on 5 June, “we need more resources, forces and capabilities so that we are prepared to face any threat, and to implement our collective defence plans in full. We will need significantly higher defence spending. That underpins everything.”

The question now remains whether all members will commit to the new goal. And, perhaps more importantly: how did we get to this point?

In Alliance for Defence

The North Atlantic Treaty Organization (NATO) was founded in 1949 to deter Soviet aggression. Its core principle—found within Article 5—states that an attack against one NATO member is to be considered an attack against all NATO members. 

Despite the Soviet Union’s collapse in the 90s, NATO not only endured but expanded. Originally 12 members, it has grown to 32, with half of those joining after the fall of the Berlin Wall. Russia’s invasion of Ukraine, and the annexation of Crimea in 2014, have made NATO’s original purpose newly relevant. Formerly neutral states like Sweden and Finland, wary of Russian aggression, have sought protection by recently joining their NATO allies.

Some critics argue that blaming Russia alone for today’s East-West tensions overlooks deeper roots. While Moscow, to many, undeniably launched the war in Ukraine and have obstructed ceasefire efforts, NATO’s expansion into Eastern Europe—including former Warsaw Pact countries—was long seen by Russia as a threat. The Warsaw Pact, a Soviet-led military alliance during the Cold War, dissolved in 1991, but many of its members later joined NATO. Many of these states border Russia.

Still, the reality is clear: Ukraine is fighting for its survival, backed by many NATO countries, against a Russian regime determined to subjugate it under the pretext of “denazification.” This propaganda, steeped in conspiracy theories, has been widely discredited as false and lacking any basis in international law.

As NATO’s strategic focus sharpened in response to renewed threats, questions around military readiness and burden-sharing among allies became increasingly prominent.

The 2 Percent Target, Theoretically

One of NATO’s core responsibilities, beyond being prepared for any Article 5 scenario is for each member to allocate a significant share of its GDP to defence. A 2 percent target was introduced as an informal benchmark in 2002 and became an official guideline in 2014.

Still, until 2024, fewer than half of the member states had actually met this target. That changed in response to the growing threat from Russia. Military analysts warn that Moscow may be preparing for a future attack on NATO territory. In 2024, for the first time, NATO members collectively spent around 2.71 percent of their GDP on defence on average.

The United States, with an economy far larger than any other member, accounted for the lion’s share. In 2024, it spent $967.7 billion on defence—roughly 3.4 percent of its GDP.

Although the 2 percent benchmark is now widely being met, discussions are already underway to raise the target to 5 percent.

So, what changed?

The U.S. Under Donald Trump 

The question of why the debate has so quickly shifted toward a 5 percent defense spending target can be summed up in two words: Donald Trump.

To be fair, Trump was not the first U.S. president to criticise NATO members for not spending enough on defence—Barack Obama and George W. Bush did as well. But Trump’s conduct on the international stage, combined with his so-called “authoritarian” tendencies at home, has sparked serious doubts about the reliability of the U.S. as an ally. At times, it seemed less like the U.S. was offering a protective umbrella and more like it was threatening to use it as a leverage against its partners.

His public berating—some would say bullying—of Ukrainian President Volodymyr Zelenskyy, during his White House visit, marked a turning point. For many Western leaders, it was a wake-up call to a new and more uncertain reality.

Trump has previously called for increased defence spending. However, in his second term, his administration appears more unified and determined to implement policies that depart from traditional transatlantic ideals of trust and cooperation. 

Trump’s stance in 2025 was clear: “I’m also going to ask all NATO nations to increase defence spending to 5 percent of GDP, which is what it should have been years ago,” he declared in January.

The initial reactions were mostly dismissive. Not even the U.S. was spending that much. While leaders agreed on the need to invest more in defence, 5 percent seemed out of reach— a completely unrealistic goal.

Times of Change

Less than five months later, however, the situation has shifted.

Prominent voices, such as Germany’s Foreign Minister Johann Wadephul and Defence Minister Boris Pistorius, have signalled openness to the 5 percent target. This is surprising, given that Germany’s new government is not unified on the issue. Yet the potential commitment of Germany, one of Europe’s leading powers, illustrates how far the debate has progressed.

However, as U.S. Defense Secretary Pete Hegseth said at a recent meeting: “There are a few countries that are not quite there yet.” He added, “We’ll get them there.”

Countries in close proximity to Russia, like Poland and the Baltic states, already spend well above 2 percent of their GDP on defense. Others, such as Spain and Italy, remain hesitant and are considered holdouts on the proposed increase. U.K. Prime Minister Sir Keir Starmer did not endorse the 5 percent goal but proposed a compromise of 3.5 percent. The summit at the end of June will be a decisive moment, the Trump administration unlikely to back down from its demands.

To be discussed is what actually counts as “defence spending.” There is a significant difference between narrowly defining it as investments in the military and weapons, or adopting a broader understanding of “defence.” In Germany, for example, investments in the country’s partly deteriorating rail and road infrastructure could be argued as essential for military mobility and logistics.

Additionally, Mark Rutte has suggested that support for Ukraine should also be counted toward the percentage goal. This approach would account for a substantial share of defence-related spending in countries such as Germany, the U.S., and Poland.

No Time for Pacifists 

The world changed with Russia’s invasion of Ukraine. In December 2024, Mark Rutte called for a “wartime mindset”—a chilling term for anyone still trying to hold on to pacifist values. The illusion has been broken, and with Europe at war, many leaders agree this is a realistic and sensible approach.

It is both understandable and important that doubts and concerns about how quickly public discourse is shifting toward increased defence spending are raised. In this case, it may simply be a more palatable way of describing militarisation.

For now, the voices strongly supporting greater investment in defence—often backed by military experts who perceive a real threat of a Russian attack on NATO territory—appear to have won this public debate.

To what extent the Zeitgeist has truly shifted, however, remains to be seen. The NATO summit in The Hague may offer some answers—though many questions will likely remain.