Rail transport cannot erase the U-boat basing problem

One proposed workaround bypasses the North Sea by breaking submarines into sections and carrying them by rail to France. That solution transfers the problem to occupied French yards, which would have to rebuild the boats to a dependable standard for crews going to sea. Coerced workers and an occupying power have weak foundations for the trust required by submarine construction. Even successfully reassembled boats still need secure routes into the Mediterranean or toward North Africa. The example shows how geographic containment consumes railway capacity, shipyard effort, time, and confidence rather than disappearing through an engineering workaround.