Security researcher in conversation Europe is arming up - but is that enough against Putin?

Stefan Michel

24.2.2025

Europe is arming itself. But will it be enough to deter potential adversaries if the USA withdraws its security guarantees? (Archive image)
Europe is arming itself. But will it be enough to deter potential adversaries if the USA withdraws its security guarantees? (Archive image)
Philipp Schulze/dpa

If Trump is serious, Europe will soon have to manage without a US security umbrella. To deter potential adversaries militarily, the continent will have to rearm massively. ETH researcher Gorana Grgić explains what is important now.

No time? blue News summarizes for you

  • Can Europe defend itself militarily or deter a potential military aggressor if the USA no longer acts as a security guarantor?
  • European countries must significantly increase their defense spending and efforts, as Russia is currently investing more, says security policy researcher Gorana Grgić.
  • In order to act effectively as a military power, the European armies must also make their weapons systems compatible, says the researcher.
  • Economically and in terms of population, Europe is strong enough to deter Russia.
  • The USA would also lose a lot - both economically and militarily - if it gave up its alliance with Europe, argues Grgić.

Even before the end of the Second World War, the Soviet Union and the USA agreed who had military supremacy in which part of Europe. The USA has guaranteed Europe's security for 80 years. The end of the Cold War did nothing to change this, even though the main enemy no longer posed a major threat.

Putin has proven that he is prepared to send his country into offensive warfare, and not just with the invasion of Ukraine. Since the war of aggression against Kiev, it has been widely believed that he could go after the next country after Ukraine - perhaps even an EU member state.

The Biden administration has maintained the transatlantic security alliance and the US Congress has approved large-scale arms aid for Ukraine.

Europe is arming itself - but is that enough?

Europe's need to do more for its own security is not a new demand from the USA. But now Trump is threatening to close the security umbrella over Europe. His approach to Putin is seen by renowned actors and observers as an invitation to exploit his military weakness.

The states with a border to Russia and especially those with a history of Kremlin hegemony have already increased their defense spending, such as Poland and the Baltic states.

But even Denmark, although it has no direct border with Russia, is increasing its defense budget by 25 percent from 2024 to 2025 - or from 2.4 percent of GDP to 3 percent. In other European countries - not least Switzerland - the defense budget is growing.

The question is what it will take for European countries to credibly deter a military power like Russia from attacking their own territory. Not only financially, but also organizationally and strategically.

Gorana Grgić researches transatlantic security at the Center for Security Studies at ETH Zurich. She knows what Europe will be missing if the USA withdraws as a security guarantor.

Europe must finally take care of its own security, is one of the recurring statements of the new US administration. Is the time of the US security guarantee really over?

There is a sense that tectonic shifts are taking place, and recent statements by key US politicians - from the President and Vice President to the Secretary of Defense - have raised serious doubts about the US commitment to European security. These statements are the strongest wake-up call yet for Europeans to take responsibility for their own defense.

The ultimate test, however, would be a crisis in which NATO's obligations under Article 5 - the Alliance case - would be invoked. Fortunately, this has not yet happened. In any case, the new tone of the statements by US officials is sobering.

The disadvantages for Europe are obvious. Would the end of this transatlantic security alliance also have disadvantages for the USA?

America's greatest geostrategic advantage since the Second World War is its unrivaled global network of security relationships. NATO forms its core and is the most institutionalized form of multilateral alliance - unlike, for example, the system of hubs and spokes in East Asia and the Pacific.

The only time Article 5 was invoked was in 2001, after the September 11 attacks, when NATO countries backed the United States in the intervention in Afghanistan. Militarily, NATO's alliance structure gives the United States a preeminent role in setting the agenda, planning and conducting operations. In addition, U.S. security commitments have been shown to have a significant positive impact on U.S. bilateral trade.

Defense spending by many European countries is already increasing. How much more is needed to deter states like Russia and prevent acts of war against European states?

There is no fixed figure, as the level of spending required depends on the threat assessment and the perceived credibility of deterrence. It is clear that the former target of 2 percent defense spending of GDP, which was once targeted as an upper limit, is now considered a minimum. In simpler terms, it is now seen as a lower limit and no longer an upper limit.

Many defense experts and policymakers argue that the threshold should be raised to at least 3 percent to ensure a credible deterrent. The level of concern varies across Europe, with border states, especially Poland and the Baltic states, naturally feeling more vulnerable and investing more accordingly.

Gorana Grgić
Center for Security Studies ETH Zürich

Political scientist and macroeconomist Gorana Grgić conducts research at the Center for Security Studies at ETH Zurich as well as at other universities and think tanks in Washington DC and Sydney.

Apart from funding, what are the biggest challenges for Europe to actually stand up to Russia militarily?

The biggest challenges lie in coordination and avoiding duplication. It is also crucial for collective defense that national defense systems can be used by the armies of different countries - in other words, that they are compatible. For example, the standardization of equipment would increase operational effectiveness and reduce inefficiencies.

Can you give an example of the interoperability of defense systems and explain why it is so important - and so difficult to achieve?

At the beginning of the Russian invasion of Ukraine, European countries had more than five times as many different weapon systems as the United States in certain categories, such as main battle tanks, fighter jets, submarines and different types of ammunition. This kind of fragmentation has made logistics, maintenance and cross-border cooperation considerably more difficult.

To achieve interoperability, the European armed forces would have to introduce standardized weapon systems in all member states, which is obviously a challenge given existing national procurement policies and the interests of the defence industry.

How many years would it take for European countries to build up their military capabilities to a level equal or superior to Russia's?

The timetable depends on how military capacity is measured. Russia's defense spending is increasing at a pace that is outpacing the combined efforts of European states, even as they seek to increase their budgets and rearm. According to the International Institute for Strategic Studies IISS, Russia's military spending will amount to the equivalent of 145.9 billion US dollars in 2023, which is equivalent to 6.7 percent of GDP and represents a year-on-year growth of over 40 percent. In contrast, Europe's defense spending will total USD 457 billion in 2024, an increase of more than 50% since 2014.

However, adjusted for purchasing power parity - how much the respective countries can procure per dollar of armaments - Russia's real defense spending is estimated at USD 461.6 billion, which is higher than that of all European countries combined.

«Russia's real defense spending is higher than that of all European countries combined.»

Is it just a question of who invests more?

It is crucial to examine how this spending translates into effectiveness on the battlefield. Russia has not been able to achieve its strategic goals since the large-scale invasion began in 2022. Furthermore, the GDP and population of European NATO states far exceeds that of Russia, so the capacity to defend and deter against Russia's militarism and aggression is absolutely there.

Great Britain and France are nuclear powers. How much does that contribute to deterrence?

The nuclear arsenals of France and the UK play a crucial role in deterring Russian aggression. They complement the US nuclear umbrella by filling gaps in extended deterrence and providing additional security to European allies. There are currently many calls for greater cooperation between London and Paris in order to reassure Europeans more effectively.

What is the impact of the EU's Common Security and Defense Policy (CSDP) on Europe's military strategic capacity?

The real question here is whether the CSDP has succeeded in advancing the integration of defense efforts. Much is still unfinished and under development.

Europe could also be forced to secure a ceasefire or a peace agreement in Ukraine. Can Europe simultaneously provide a large peacekeeping mission and deter a potential aggressor militarily?

As recent debates at an emergency summit in Paris have shown, European heads of state and government are still divided on the future deployment of peacekeeping troops. While some countries have argued in favor of discussing a possible European-led peacekeeping mission, others remain reluctant due to the risks of escalation and the strain this could place on NATO.

It is generally expected that a large European peacekeeping contingent will be available in the event of a ceasefire or peace agreement. However, the composition, mandate and size of such a force remain uncertain, as they would depend on the security conditions on the ground, the level of American involvement - behind which there is currently a big question mark - and Russia's attitude after a possible ceasefire.

What does this mean for the possible simultaneous securing of a ceasefire in Ukraine and the European eastern border?

A key concern is to ensure that any peacekeeping mission is adequately protected and does not inadvertently encourage Russian aggression by overstretching European military resources.

What do you think is the better option for Europe: to invest heavily in European arms production or to buy more from foreign manufacturers, for example in the USA, South Korea and other countries?

The first EU strategy for the defense industry (Defense Industrial Strategy, EDIS), which was published last year, has already addressed this issue. The strategy sets ambitious targets for joint development and procurement to reduce dependence on external suppliers. It outlines a long-term vision for improving European defense readiness. The logic behind the focus on domestic production is that a more integrated European defense market would reduce costs and improve strategic autonomy. However, these efforts are hampered by geopolitical factors.

In what way?

Some European experts argue that buying key US weapons systems and ammunition could strengthen Europe's negotiating position with Washington and help prevent less favorable security outcomes.