European rearmament has spent three years learning from the cheapest weapon on the battlefield and is now discovering the price of the most expensive one. Unmanned systems have become indispensable for reconnaissance, attrition, deception, saturation and, increasingly, interception, and nothing in the evidence of the past year suggests that role is contracting. The harder question is a different one, and it is financial as much as military: whether inexpensive unmanned mass can substitute for the complex weapons that deliver or prevent high-end effects at operational and strategic depth. Those weapons — cruise missiles, ballistic missiles, anti-ballistic interceptors, and the radars, command systems and data links without which none of them functions — are bought in small quantities, qualified slowly, and manufactured through supply chains that cannot be enlarged by adding final assembly alone. The war that made drones famous has also made them a poor guide to the constraint that now binds European forces. That constraint is not the number of airframes the continent can build but the number of high-performance effectors it can hold, replace and command at the rate a high-intensity campaign consumes them. Whether Europe is building that depth, and what would have to be true for the attempt to succeed, is the question the procurement and financing decisions of 2026 have begun to answer.