Executive Summary The U.S.–Israeli military campaign against Iran has revealed a familiar but widening gap between Washington and its European allies. While most European governments have expressed political support and provided limited logistical assistance, few are prepared to participate militarily in the conflict. This cautious stance reflects a combination of domestic political constraints, economic vulnerabilities, and strategic risk calculations. Spain’s refusal to allow U.S. air tankers to operate from its bases, contrasted with Germany’s more supportive posture, illustrates the diversity of European responses. Yet Germany remains an exception. Across Europe, including in traditionally pro-American countries such as Poland, governments are reluctant to engage directly in another Middle Eastern war. Poland’s case is particularly instructive. Despite its long-standing strategic partnership with the United States and its participation in previous American-led interventions in Iraq and Afghanistan, Warsaw is unlikely to join the current military effort. Beyond domestic political considerations, Poland’s historically distinctive relationship with Iran provides an additional reason for caution. Europe’s limited involvement reflects broader structural factors: the legacy of past Middle Eastern interventions, domestic political constraints, economic vulnerabilities, and diverging threat perceptions within the transatlantic alliance. Introduction: Europe’s Reluctant Alignment The military campaign launched by the United States and Israel against Iran in February 2026 has reopened a recurring question in transatlantic relations: how far European allies are willing to follow Washington into military confrontations in the Middle East? The diplomatic tensions surrounding the conflict illustrate the problem. When the Spanish government refused to allow American air tankers to use the bases in Morón and Rota for operations related to the war, the reaction from Washington was swift. President Donald Trump publicly criticized Madrid and threatened economic retaliation, reviving a familiar logic of alliance politics: “You are either with us or against us.” On the same day, however, the tone in Washington was markedly different during a meeting between President Trump and German Chancellor Friedrich Merz. Merz offered clear political backing for the U.S. position and avoided criticizing the military campaign. Unlike Spain, Germany did not rule out the possibility of military participation. Yet Germany’s stance remains an exception rather than a reflection of a broader European consensus. Across the European Union and the United Kingdom, governments have largely limited their response to logistical assistance and political expressions of solidarity, avoiding direct participation in military operations. This pattern reflects not only diplomatic caution but also deeper structural constraints shaping European foreign policy. Europe’s Strategic Caution European reluctance to participate militarily in the conflict stems from several interrelated factors. First, public opinion across Europe remains deeply skeptical of military interventions in the Middle East. The experiences of Iraq and Afghanistan continue to shape political attitudes toward overseas military engagements. For many European voters, those conflicts demonstrated the risks of long and costly interventions with uncertain outcomes. Second, economic concerns play an important role. European governments fear that a prolonged confrontation with Iran could disrupt global energy markets, increase inflationary pressures, and undermine already fragile economic recoveries. Instability in the Gulf could also affect maritime trade routes that are critical for European economies. Third, domestic security considerations reinforce caution. Many European leaders fear that escalation in the Middle East could trigger new migration flows toward Europe and increase the risk of terrorist attacks linked to Iranian proxy networks. These concerns explain why even governments broadly aligned with Washington have chosen to limit their involvement to political support and logistical cooperation, rather than direct military participation. Spain, Germany, and the Politics of Alliance The contrast between Spain and Germany illustrates the range of European responses. Spain’s refusal to allow American aircraft to use its bases reflects both domestic political calculations and broader strategic caution. Public opinion in Spain is strongly critical of the current U.S. administration and highly sensitive to developments in the Middle East. Surveys indicate that large majorities of Spanish citizens view President Trump negatively and hold deeply critical views of the situation in Gaza. For Prime Minister Pedro Sánchez, resisting American pressure therefore carries clear domestic political advantages. Conversely, aligning too closely with Washington could impose significant electoral costs. Historical memory also plays a role. The 2004 Madrid train bombings, carried out by jihadist extremists after Spain’s participation in the Iraq war, remain a powerful reminder of the potential domestic consequences of involvement in Middle Eastern conflicts. Germany, by contrast, has adopted a more supportive posture toward Washington. Chancellor Friedrich Merz’s statements reflect Berlin’s desire to maintain close transatlantic ties and demonstrate reliability as a strategic partner. Nevertheless, even in Germany, the prospect of direct military participation remains politically controversial. Taken together, these examples illustrate a broader European trend: political support for the United States without a strong appetite for direct military engagement. Poland: Loyalty, Memory, and Strategic Priorities Poland’s position highlights the complexity of this dynamic. Warsaw has long been one of Washington’s closest allies in Europe. Poland strongly supported U.S.-led interventions in Iraq and Afghanistan and played a significant role in both operations. During the 2003 invasion of Iraq, it was one of only four countries, alongside the United States, the United Kingdom, and Australia, to contribute ground forces in the initial phase of the campaign. Polish troops later participated in major combat operations, including the defense of Karbala City Hall in 2004. In Afghanistan, Poland commanded the Ghazni province for several years. These deployments came at a considerable cost: sixty-nine Polish soldiers were killed during operations in Iraq and Afghanistan. Today, however, Poland faces a very different strategic environment. Russia’s ongoing war against Ukraine dominates the country’s security agenda, and Polish military planning focuses primarily on deterrence along NATO’s eastern flank. Entering another distant conflict in the Middle East would therefore represent a risky diversion of resources. Poland’s historical relationship with Iran provides an additional reason for caution. In the eighteenth century, Persia was among the few states that refused to recognize the partitions of Poland by neighboring powers. During the Second World War, more than 100,000 Polish refugees evacuated from the Soviet Union found shelter in Iran, an episode that remains an important part of Polish historical memory. These ties do not translate into political sympathy for the Iranian regime. Polish governments have consistently condemned the authoritarian nature of the Islamic Republic and expressed solidarity with the Iranian people. Nevertheless, this legacy reinforces Warsaw’s preference for a cautious and measured approach to the current conflict. Conclusion: The Limits of European Military Engagement The war against Iran has once again revealed the limits of European participation in American-led military operations in the Middle East. Across the continent, governments prefer to support the United States politically while avoiding direct involvement in combat operations. Domestic political constraints, economic vulnerabilities, and differing strategic priorities all contribute to this cautious approach. Poland’s position illustrates this dynamic particularly well. Despite its strong alliance with Washington and its past participation in U.S.-led interventions, Warsaw is unlikely to engage militarily in the current conflict. Historical ties with Iran and the overriding priority of European security reinforce this reluctance. As the conflict evolves, the United States may intensify pressure on its European allies to assume a greater role. Yet unless the war directly threatens European security interests, most governments are likely to maintain their current posture: political support without military engagement.