A fleet could not cross a clean line between a war zone and a safe zone at sea. That mental model may have carried over from parts of the First World War, when German surface threats were geographically constrained and fast, zigzagging ships faced lower risk in some areas. It did not fit the Norwegian campaign, where enemy surface forces could appear beyond the supposed boundary. A carrier flag officer commanding several flight decks would provide an additional level of scrutiny and make the isolation of Glorious much harder to approve.
Notable Point · 1:08:45-1:10:03
Glorious exposed the danger of imagining a safe zone at sea
The decision to let Glorious sail with only two destroyers reflected a peacetime assumption that danger ended beyond a neat geographic boundary.