In Operation Albion, Nautilus served both as a transport and as an emergency defensive minelayer for the Baltic force. This use of mines differed from a hidden ambush: the field operated as an openly imposed barrier. A newly laid field could make a threatened stretch of water temporarily unusable, allowing Germany to concentrate forces elsewhere. If an enemy tried to force the passage, mines could inflict losses, impose delay, and provide enough warning for defenders to reorient. Deploying that barrier remained difficult with World War I technology.
Notable Point · 28:13-29:55
Emergency minefields as defensive barriers
Nautilus could rapidly turn threatened water into a barrier that delayed an enemy and concentrated friendly forces elsewhere.