German U-boats faced inescapable geographic tradeoffs. Stationing submarines near Liverpool and other western British ports made merchant traffic easier to anticipate, but also put the boats under aircraft, near minefields, and among dense escorts. Moving into the mid-Atlantic air gap reduced exposure to land-based aircraft while vastly increasing the water that patrols had to search. Dispersed boats required more communications as packs tried to assemble against convoys. Every option imposed costs the campaign could not escape. In this assessment, the campaign was generally as well executed as those constraints allowed, with some reservations about Dönitz's decisions.
Chapter · 24:43-26:25
Atlantic geography and tradeoffs
The closing argument reduces the submarine campaign to geography: close to British ports meant air cover and minefields, while the mid-Atlantic meant too much ocean to search.