Since the establishment of the North Atlantic Treaty Organization (NATO), the United States of America (USA) has arguably been a central actor in the security strategy of the alliance. This is because the US provides the vast majority of NATO’s total military capacity and is also the most important provider of the alliance’s nuclear deterrence capability. Moreover, the extensive global network of US military bases and its strategic dominance over sea lanes enable NATO to sustain military operations on a global scale. On the other hand, Europe has played an important role in security and defense since the establishment of NATO. However, the re-election of Donald Trump as president on January 20, 2025 has significantly altered global geopolitics. Under his new presidency, Trump has threatened to reduce US commitments to NATO by reintroducing the “America First” doctrine, as well as forcing European countries to finance their own defense. This has brought the European Union (EU) to a critical turning point. Although Europe has long debated the idea of “strategic autonomy”, the prospect of a NATO without the United States is no longer just a theory but a serious security challenge.
Furthermore, the debate between US President Donald Trump and Ukrainian President Volodymyr Zelensky on the 28th of February 2025 posed a major threat to European countries. This event has caused Europe to reconsider its strategic intentions due to the risk of losing US support on Ukraine and security issues. The Trump-Zelensky debate has raised uncertainties over the future of Ukraine and European security, while raising concerns in Brussels that transatlantic relations could be seriously damaged. Indeed, Trump’s announcement that he might withdraw the United States from organizations such as NATO and the UN raised concerns about the future of NATO and the security structure of Europe.
Although European countries are trying to develop new strategic approaches in response to Trump’s threats, the strategic gaps that a NATO without the US would pose significant challenges in critical areas such as defense spending, military command structures and nuclear deterrence. Despite the fact that Europe is looking for various solutions to overcome this situation, the lack of military and strategic support from the United States will lead European countries to face serious challenges in the field of security and defense. For instance, the US has provided the majority of NATO’s defense expenditures so far. This has allowed European countries to reduce their defense budgets and use the money in other areas for development. However, a limitation of this contribution by the US would force European countries to assume more financial responsibility. This shift will not only have a negative impact on budgets, but also on the infrastructure investments needed to increase Europe’s military capacity. Besides, the US plays a central role in the nuclear deterrence of NATO. The nuclear capability of NATO is largely backed by US strategic nuclear weapons. Yet, in the event that the US withdraws from NATO or does not adequately support the EU’s security policies, European countries will lose this strategic advantage. This would force European countries to develop new strategies to strengthen their nuclear deterrence against great powers such as Russia and China. However, it is unlikely that Europe will be able to formulate and implement a comprehensive nuclear strategy on its own in the near future. In this case, European countries could risk remaining vulnerable to nuclear threats.
The departure of the US from NATO could lead to significant structural changes in the command structure of the alliance. This is because the US has so far assumed a large part of NATO’s command system, managed the alliance’s military operations and played a decisive role in strategic decisions. This reduced US contribution poses a risk of creating significant disruptions in NATO’s command and control mechanisms. Such a situation could pose serious challenges for European countries in terms of ensuring military cooperation and maintaining an effective command structure within the alliance.
As the US reduced its support to Ukraine and started to advocate for its withdrawal from NATO, European countries started to develop their own solutions. Especially leading European countries such as Germany, France and the UK have taken a number of diplomatic and military steps to free Europe from its dependence on the US. One of these steps has been to increase support for Ukraine. Meanwhile, these countries have begun to formulate strategic plans and reshape their defense policies in order to meet Europe’s security needs. In this framework, they have again put the idea of a European Army on the agenda. In this context, French President Emmanuel Macron, in line with his past stance, has begun to emphasize that Europe should build its own security autonomy by becoming independent from the US influence within NATO. Even though Macron’s stated goal of European strategic autonomy aims to strengthen the continent’s geopolitical independence in the long term, the practical obstacles encountered in the process of realizing this goal reveal how challenging and complex it is.
The first important reason for this is Germany, which is the “brain and engine” of Europe, is hesitant about the ideas put forward by Macron. Today, Germany is hesitant to increase Europe’s military capacity despite having the strongest economic power in Europe. Instead of increasing its military power, Germany prefers to ensure security through diplomatic and economic instruments. However, this attitude of Berlin makes it difficult for Europe to create a new security structure independent of NATO and the US. Moreover, Berlin’s approach does not set an example for other European countries, which instead largely align their security strategies with US policies.
Another factor is the security concerns of Eastern European countries. Countries such as the Baltic states and Poland are mainly dependent on US support to ensure their security, especially in the face of Russia’s influence and military displays of power in the region. For these countries, the weakening of NATO would pose a serious threat to their security, especially in Eastern Europe. Therefore, these countries will seek more military support to close their security gaps and counter external threats. This poses a serious obstacle to Europe’s goals of strategic autonomy and an independent European Army.
A further important factor is the lack of military infrastructure in European countries. European countries are likely to face significant challenges in modernizing and strengthening the existing military infrastructure while trying to increase their defense capacity. This is because Europe’s military power has so far been supported by the United States. With the US withdrawal, the strategic plans of many European countries are affected by the need of updating military bases, communication and logistics networks, as well as the establishment of advanced defense systems. These shortcomings limit Europe’s efforts to build an independent defense structure and increase its dependence on NATO. Hence, these shortcomings in the military infrastructure constitute a significant obstacle to the achievement of Europe’s security goals.
Ultimately, and crucially, the question of which country will be at the helm of the planned strategic autonomy and independent European Army has yet to be clarified. Today, even though the EU and its member states have decided to increase their defense budgets, these decisions not only increase financial resources, but also create uncertainties about which country or countries will assume the leadership role and who or who or whom will be the main actors to shape Europe’s defense policies. Efforts to establish strategic autonomy and an independent military in Europe are also complicated by the balance of power and leadership contests among member states. This uncertainty constitutes a major obstacle in the process of strengthening Europe’s security and defense structure.
In parallel with the global security threats, economic challenges and geopolitical shifts they face, European countries have recently sought alternative solutions. In particular, the uncertainties in the global strategic role of the United States and the changing dynamics within NATO require Europe to develop new approaches to its security and foreign policy decisions. In this context, the EU and European countries have not only reviewed their traditional alliances with the US, but also started to plan for deeper cooperation with strategic partners such as Türkiye on regional security issues. Indeed, Türkiye’s geographical location, military capacity, military equipped with modern technologies and regional influence make it an indispensable actor for Europe’s security. Specifically, its influence in geopolitically critical regions such as the Middle East, the Caucasus and the Mediterranean makes Türkiye not only a regional power but also a strategic partner for European security.
In addition, the EU’s development of its defense industry and its steps to increase military expenditures are increasing the importance of potential partnerships with Türkiye. By strengthening its cooperation with the EU as a NATO member, Türkiye has the ability to offer effective solutions to European challenges in regional security and crisis management. This reinforces the strategic role of Türkiye in shaping Europe’s security strategies. Also, Türkiye’s position within NATO constitutes an important counterweight for European security. However, the prospect of NATO’s weakening creates new power gaps in European security. At this point, Türkiye has the potential to serve as a bridge between the EU and NATO members.
Notably, Türkiye is located as a balancing power against Russia’s growing geopolitical influence in the Middle East, the Caucasus and the Eastern Mediterranean. In this regard, the military capacity and diplomatic moves of Türkiye are among the key elements that can determine the direction of European security policies. Türkiye has the potential to develop deeper strategic cooperation with Europe while shaping its independent defense strategy in line with the transformations in the global security environment. The development of its defense industry and the increase in its military capacity bring opportunities to develop joint projects and increase security cooperation with the EU.
On the other hand, the declining influence of the US on European security is forcing Europe to develop its own independent security strategies. In this process, factors such as increasing military spending, deepening cooperation and strengthening the EU’s defense infrastructure become prominent. In this respect, the inclusion of Türkiye in the process may help to build the European security structure on more solid bases. Nevertheless, this integration should not be limited to the military sphere, but should be expanded to include diplomatic and economic dimensions as well. Thus, for the EU, the inclusion of Türkiye in the Union could be a step that would contribute to building regional and global security on solid bases.
