How should the Union and its members react – and how far should they be prepared to go? Are member states willing to incur the political and economic costs required to defend their collective interests and fundamental values? What risks does the Greenland crisis pose for NATO and for the Union’s internal cohesion and credibility? How will the crisis affect ongoing efforts to achieve peace in Ukraine? Does the confrontation offer strategic openings for other geopolitical actors, such as Russia and/or China, to exploit widening divisions among transatlantic allies? And, ultimately, what does this episode imply for Europe’s long-term security architecture, its dependence on US guarantees, and its ability to defend its interests in the Arctic and beyond?