British war planning had not accounted for France falling or for the naval assets that would disappear with it. A French collapse could appear unlikely while still carrying enormous consequences for Britain. Those consequences should have justified planning for replacement capability, but the necessary provision was absent from British force structure. Norway provides a similar example, although the way its government had managed the armed forces during the 1920s and 1930s made its vulnerability less improbable than planners might wish.
Notable Point · 16:43-18:11
France's fall was a low-probability, high-impact naval risk
British plans assumed French naval assets would remain available and did not hedge against the unlikely but catastrophic loss of France.