For the first time in generations, Germany is rebuilding its military might — not in defiance of Europe, but in response to a fraying American guarantee and a resurgent Russian threat. Yet history does not wait politely at the door: when Berlin speaks of fielding the continent's strongest conventional army, Paris and Warsaw hear older languages beneath the new vocabulary. The question Chancellor Merz must answer is not whether Germany can rearm, but whether it can do so in a way that reassures rather than reawakens the anxieties that shaped the postwar order.