Europe’s ability to operate combat aircraft in contested airspace cannot be measured by counting anti-radiation missiles or the aircraft nominally assigned to the mission. Suppression of enemy air defences is produced by a chain that begins before a weapon is released and continues long after a platform has entered service. Emissions have to be collected and characterised, threat and mission data validated, software and countermeasures updated, aircraft and effectors integrated, and every change tested and accepted without introducing unacceptable risks elsewhere in the weapon system. A state can own the aircraft and the weapon and still depend on another party for the data that makes them useful, the authority to modify their software or the facilities needed to qualify a new configuration. The European rearmament problem is therefore not only whether France, Germany or Britain can buy new aircraft and electronic-warfare equipment. It is whether European authorities control enough of the information, software, interfaces, engineering organisations, test infrastructure and weapons to turn those purchases into a renewable military capability.