The defence sector is growing fast and needs to integrate partners, scale collaboration and make AI usable quickly. Cloud and AI services speed this up, but choices made only for speed can create long-term dependencies on data control, providers and availability. Drawing on decades of digitalisation in other industries, the talk argues that sovereignty does not mean avoiding the cloud. It means deciding on purpose which data, workloads and capabilities go to the cloud and which stay under direct control. The same applies to AI: cloud AI gives fast access to strong capabilities, while local AI protects sensitive data and keeps critical functions running when cloud access is lost.