Intelligence and the ‘Mindset’: The German invasion of Norway in 1940

‘Weserübung’, the German invasion of Norway and Denmark on 9 April 1940, was a brilliantly successful surprise attack, both strategically and tactically. Strategic surprise was obtained because the idea that Germany was about to launch a major invasion of Norway was remote from any of the preconceived scenarios about Germany's next move. Germany's achievement of tactical surprise was also aided by bad weather in the North Sea. The main reason for the failure of both Norwegian and British policy-makers to comprehend what the Germans were up to lies in the importance of the ‘mindset’. On both sides of the North Sea the conventional wisdom was that Germany would not attempt an invasion of Norway against the supremacy of British sea power. Hence all incoming information was interpreted in Oslo in the light of the next mindset, namely that only a determined British attempt to take control of the Norwegian coast could trigger an armed German retaliation. In London, incoming intelligence was interpreted so as to conform to the Admiralty's preconceived scenario of a German naval breakout into the North Atlantic.     

Franco-German Intelligence Cooperation and the Internationalization of Algeria's War of Independence (1954–62)

Between 1958 and 1960, the French domestic security and intelligence services came to establish a close, multi-layered, and secret working relationship with their German counterparts. The purpose of this collaborative arrangement was to enlist German support in combating the subversive activities of the Algerian Front de Libération Nationale, whose members had taken refuge in Germany. In particular, the metropolitan authorities sought to impose on their German counterparts some of the same methods of colonial policing and intelligence that characterized their own counter-insurgency in France. These efforts proved counter-productive, however, for in internationalizing the Algerian war, they drew public attention to the colonial nature of France's hold over Algeria.     

Intelligence and diplomatic signalling during crises: The British experiences of 1877–78, 1922 and 1938

The roles of intelligence, communications and signals in crisis decision-making routinely are mentioned in passing but rarely assessed in detail. This study examines these issues in three international crises: the great eastern question, 1877–78, Chanak, 1922 and Munich, 1938, and briefly compares these findings to two others, July 1914 and Cuba, 1962. It demonstrates that intelligence, communications and signals are more problematical in crises than is generally believed. This study challenges the conventional view that crises are essentially something to manage. Instead, it argues, crises are explosive, unpredictable and high in risk, dominated by emotion, factionalization, communication failures, missed signals and unintended consequences.     

‘One of our Most Valuable Sources of Intelligence’: British Intelligence and the Prisoner of War System in 1944

During the Second World War, secret information derived from enemy prisoners of war (POWs) was a valuable asset to British intelligence. Until 1944, the POW system had expanded from a small interrogation camp in the Tower of London to a multi-step structure with the so-called Combined Services Detailed Interrogation Centre, United Kingdom (CSDIC(UK)) at its top. The methods employed to collect reliable information included microphones, stool pigeons and different interrogation techniques. The results were read by all services and several ministries which provided a unique insight into German capabilities, intentions and thoughts.     

The Institution of Modern Cryptology in the Netherlands and in the Netherlands East Indies, 1914–1935

The need for Communications Intelligence in the Netherlands was first felt by the Dutch military as a consequence of the outbreak of the First World War. The decision to prolong, as in the Netherlands, or establish, as in the case of the East Indies, COMINT facilities belonged to the judicial domain and was primarily related to threats posed by revolutionary movements from within the country. The monitoring of traffic from foreign embassies or consulates happened only when interference from foreign governments was suspected. Japanese expansionism, leading to direct Japanese involvement in the political developments in the East Indies, provided such a case. As a consequence, the fine line between domestic and foreign affairs became thinner still until it entirely vanished during the later part of the 1930s.     

Intelligence and the formulation of policy and strategy in Early Modern Europe: The Spanish Monarchy in the Reign of Charles II (1665–1700)

This article seeks to explore the means whereby the Spanish Monarchy under the last Habsburg, Charles II (1665–1700), contributed to its own survival in the era of Louis XIV by exploring its acquisition and use of intelligence. There was nothing particularly distinctive about Spain's intelligence machinery. Nor was it always effective. Nevertheless, Spain's extensive diplomatic and imperial network facilitated the acquisition of a great deal of information which on occasion was clearly of great importance – for example, in preventing the destruction of Charles II's fleet in the summer of 1693 by that of Louis XIV. In sum, intelligence contributed to the remarkable resilience of the Spanish Monarchy in an age of supposed Spanish decline.     

Diplomatic Sigint and the British Official Mind during the Second World War: Soviet claims on Turkey, 1940–45

Historians of Soviet foreign policy have recently revisited the issue of Soviet claims against Turkey: a Stalinist objective during the period of the Nazi–Soviet Pact and in the immediate post-war era. Recently opened archives show that the British response to Soviet claims in 1945 was driven by comprehensive access to Turkish diplomatic correspondence. However, the British failed to recognize wartime decrypts that indicated continuity in Soviet ambitions in Turkey since 1940. This failure reflected the responsibility of the operational departments of the Foreign Office for the assessment of diplomatic Sigint, and the absence of a genuine political intelligence department with eyes for anything other than current lines of policy.     

International Cooperation and Bureaucratic In-fighting: American and British Economic Intelligence Sharing and the Strategic Bombing of Germany, 1939–41

The pursuit of intelligence on the German economy by the United States Army Air Corps prior to 1942 revealed great gaps in US knowledge of the German economy. This encouraged joint efforts with British Intelligence. The Air Corps exploited sources creatively to find German industrial targets. Its specialized needs persuaded it to try to establish an Air Corps intelligence gathering section. The Air Corps clashed with the Army over access to economic data. Its need for economic intelligence merged with its political goal of making strategic bombing its primary mission. Intelligence gathering efforts ultimately translated into the creation of air warfare strategy.     

The Royal Navy,Intelligence and the Spanish Civil War: Lessons in Air Power, 1936–39

This article discusses the Royal Navy (RN)—Royal Air Force (RAF) feud concerning the use of air power in the round through an investigation of each service's appreciations of the lessons being learned about air power during the Spanish Civil War. It reveals that despite such bodies as the Joint Intelligence Committee existing, for the processing of operational and strategic intelligence, there was very little that was joint about the way air power lessons were being used to inform RN and RAF interwar preparations for future conflict. Not only were the RN and RAF rivals, which dragged out the process and skewed the results so that they became useless for planning, but in that non-joint age each service could use the results for its own separate purposes and avoid any synergy among the services for operational and strategic effectiveness.     

Security Intelligence in the Middle East (SIME): Joint Security Intelligence Operations in the Middle East,c. 1939–58

Security Intelligence Middle East (SIME) remains an understudied aspect of British intelligence. In many respects it was a remarkable organization. Its wartime iteration was created in haste, ostensibly as a military body but based upon the Security Service's office in Cairo. It evolved into a truly ‘joint’ unit but culturally was closer to the Security Service (MI5) than either the military or the Secret Intelligence Service (MI6). SIME changed dramatically as a result of the end of the Second World War: it became the sole responsibility of MI5; local cooperation between MI5 and MI6 was scaled-down and became the focal point of a broader inter-intelligence service dispute in London; and new nationalist threats caught SIME off-balance and eventually undermined its raison d'être. SIME's contrasting wartime and peacetime iterations provide a useful example of how intelligence agencies respond to external pressures. It also provides a window into wider jurisdictional and constitutional conflicts at the heart of the relationship between MI5 and MI6, both during and after the war. Finally SIME shows practitioners what can be achieved under the right stimulus and what can be lost when that stimulus fades.