This session will discuss how the foundations of the post-Second World War transatlantic alliance are under increasing strain. With a second Trump administration back in office, long-standing assumptions about U.S. - Europe relations are being challenged. Even Atlanticists, such as German Chancellor Friedrich Merz, have conceded that Europe can no longer rely on the United States for its security. Trade tensions, divergent strategic priorities, and shifting global power dynamics, particularly in relation to Ukraine, underscore the urgency of rethinking Europe’s position on the world stage. The plenary will examine the implications of the evolving transatlantic relationship and ask: what should Europe's strategic response be in this uncertain new era?