The strategic plans produced by the great powers before the First World War were abstract, ambitious and largely unrealistic. When British, German and Soviet strategists returned after 1933 to consider the role of Scandinavia in a future war, they did so in the light of experience which their predecessors had lacked. There appear to have been no serious examinations of the possibility of military operations on Scandinavian territory of the kind which loomed so large in pre-1914 deliberations. The primary focus was on economic and naval warfare. For both Great Britain and Germany, the lesson of the last war was that economic pressure on Germany had been of decisive importance. Moreover, in the light of Germany's territorial losses after Versailles and the exploitation of new mineral resources in Scandinavia, it was reasonable to assume that Germany's economic dependence on indigenous Scandinavian products would be greater in both relative and absolute terms than it had been in 1914–18. Scandinavian resources would also be of great importance to Great Britain, but its geographical position, naval superiority, financial resources and world-wide empire would give Britain access to alternative sources of supply and the capacity to deny such access to Germany. Britain's principal aim in wartime would therefore be to enlist the Scandinavian countries in an economic blockade. Germany, by contrast, would require only business as usual.

The logic of British strategy meant not only that the machinery of economic warfare, with all that this implied for the Scandinavian neutrals, must be applied from the very outset, but also that neutrality itself was dispensable.