A 2,017-ton German submarine appeared off the northern tip of Scotland during a recent military exercise, giving British commandos a staging platform to reach shore by inflatable boat, ascend rocky cliff faces, and direct the guns of a 401-foot Portuguese frigate at targets inland. The drill showed how allied forces carry out covert landings from submarines in difficult shoreline environments.

The exercise brought together several NATO partners, combining submarine operations with direct cliff assaults in a live exercise environment. Scenarios like this are growing in number as NATO focuses on amphibious and covert capabilities.

Separately, the Australian Naval Institute flagged risks about unstable logistics pipelines underpinning nuclear submarine programs, a warning that creates new urgency to long-term procurement planning for Australia's future submarine fleet. Analysts say supply chain resilience will be critical as Australia works toward fielding nuclear-powered submarines.