ON Semiconductor Czech Republic merits attention not because it sits at the visible end of the defence market, but because it occupies a more decisive industrial position beneath it: the provision of power-semiconductor manufacturing capacity on European soil. In an environment where strategic autonomy increasingly depends on control over enabling technologies rather than only over finished platforms, the company represents a relevant case of how semiconductor fabrication, materials processing, and power-device capability intersect with deterrence, procurability, and supply-chain resilience. Its importance lies in the ability of locally embedded production to support the wider defence-industrial base, reduce exposure to external bottlenecks, and strengthen the technological foundations on which interoperable military systems depend. That relevance is sharpened by the fact that European policy is moving from broad resilience objectives towards harder autonomy conditions, making companies such as ON Semiconductor Czech Republic strategically significant not only for what they manufacture, but for how their industrial configuration fits the emerging logic of European defence sovereignty.