The annual NATO summit ended with fresh questions about the future of the alliance after US President Donald Trump changed his tone several times during the high-level meeting. His shifting comments left many allies unsure about the direction of US foreign policy and raised new debate about the strength of transatlantic ties. At the start of the summit, Trump spoke in a sharp and critical way. He expressed frustration over the situation in the Middle East and said the temporary ceasefire with Iran had failed to bring lasting calm. He also criticized several NATO members and repeated his long-standing demand that allies increase their defense spending. Trump again argued that the United States should not carry the largest financial burden for the alliance. He urged member states to meet higher military spending goals and said every country should do more to protect shared security. His remarks echoed comments he has made during previous NATO meetings. The president also criticized Spain after its government showed resistance to the proposed defense spending target. He suggested that trade relations could face pressure if allies failed to support shared security goals. Trump also repeated his interest in Greenland, a self-governing territory within the Kingdom of Denmark, a position that has drawn attention in past years. Only hours later, Trump's message changed. After meeting with NATO leaders behind closed doors, he described the discussions in positive terms. He said the meeting showed unity and praised the atmosphere among alliance members. His comments surprised many observers because they followed several hours of criticism. The warmer tone suggested that private talks may have helped reduce tensions between the United States and its allies. Trump also offered positive remarks about Ukrainian President Volodymyr Zelenskyy. He praised Zelenskyy for leading Ukraine during its ongoing conflict with Russia and acknowledged the challenges facing the country. The comments marked a noticeable shift from earlier periods when the relationship between the two leaders appeared tense. Political analysts said Trump often relies on personal relationships with world leaders when shaping his public message. They noted that his views can change quickly depending on discussions during international meetings and his interactions with individual leaders. The summit host, Turkish President Recep Tayyip Erdoğan, appeared to play an important role during the gathering. Trump has often spoken positively about Erdoğan and described the relationship between the two leaders as strong. During the summit, Trump again praised Turkey and highlighted what he called a productive partnership. Observers said this personal connection may have helped create a smoother atmosphere during the event. They suggested that positive relations between the two presidents reduced the chance of deeper disagreements becoming public. NATO Secretary General Mark Rutte also worked to keep discussions focused on cooperation. Throughout the summit, he highlighted the progress made by member countries in increasing defense investment. His message stressed that many allies have responded to long-standing calls for stronger military spending. Security experts believe those efforts may have helped improve the overall mood of the meeting. By recognizing recent progress, alliance leaders were able to focus on shared goals instead of public disagreements. Despite the more positive ending, many European leaders remain cautious. Trump's changing public statements have raised concerns about the long-term reliability of US support for NATO. While the alliance remains active and continues joint military cooperation, some governments are preparing to strengthen Europe's own defense capabilities. Several member states have already pledged to increase defense spending in the coming years. Analysts believe Europe will continue to invest more in its own security while maintaining close cooperation with the United States. The summit showed that NATO remains united in its core mission, but questions about future US policy continue to shape discussions among allies. For many governments, the meeting highlighted both the strength of the alliance and the uncertainty created by changing political leadership. As global security challenges continue to grow, NATO members are expected to keep working together while adapting to new political realities. Future summits will likely remain important opportunities to strengthen trust, improve cooperation, and maintain stability across the alliance.