Twenty-five years after the attacks that briefly unified the Western world, European capitals are pausing to ask not what was lost on September 11, 2001, but what was built in its aftermath — and whether those bonds can endure without the crisis that forged them. As the United States turns inward in a period of strategic retrenchment, Europe finds itself at a quiet inflection point: honoring a shared past while quietly preparing for a future it can no longer take for granted. The trans-Atlantic alliance, once animated by shared trauma and a common enemy, must now sustain itself on something mo