A 2,017-ton German submarine surfaced off the northern tip of Scotland during a recent military exercise, giving British commandos a departure point to reach shore by inflatable boat, scale cliffs, and direct the guns of a 401-foot Portuguese frigate at targets inland. The drill showed how allied forces plan and execute covert landings from submarines in difficult shoreline environments.

The exercise brought together a mix of allied military units, combining submarine operations with overland commando movements in a realistic training scenario. Scenarios like this are becoming more frequent as NATO focuses on amphibious and covert capabilities.

Separately, the Australian Naval Institute highlighted problems about vulnerable procurement networks underpinning nuclear submarine programs, a warning that brings added scrutiny to long-term procurement planning for Australia's future submarine fleet. Analysts say consistent supplier availability will be critical as Australia works toward building out its undersea fleet.