A graduate of the Army Military Academy, Major General Antonio RUIZ BENITEZ is an officer from the light infantry units of the Spanish Legion in the Spanish territories of North Africa. In 2006, he commanded the Spanish Task Force deployed in Congo under the aegis of the European Union. Promoted to colonel in 2010, he took command of the light infantry regiment "alejandro farnesio" of the 4th brigade of the ^Spanish Legion. He is currently in charge of Spanish Army doctrine (Doctrina, Investigación, Orgánica y Materiales).

Lieutenant General Guionie spent most of his career in the marine infantry, notably in the 8th Marine Infantry Parachute Regiment. This career allowed him to acquire a rich operational experience (Chad, Cambodia, Central Africa, Bosnia, Kosovo, Ivory Coast). He commanded the 9th Marine Infantry Brigade (notably in Mali during Operation Serval) before joining various staffs. Today he is the commander of the land forces in Lille.

Olivier Zajec is a lecturer in political science and international relations at the University Jean Moulin Lyon III. He holds a PhD in the History of International Relations (Paris-IV Sorbonne), is a graduate of the École Spéciale Militaire de Saint Cyr and Sciences-Po Paris, and has been head of the geopolitics course at the École de Guerre (Paris) since 2015. A lecturer at the Institut des Hautes Études de la Défense Nationale (IHEDN) and at the Centre des Hautes Études Militaires (CHEM), he is a research fellow at the Institut de Stratégie Comparée (ISC, Paris) and deputy director of the journal Stratégique. He regularly contributes to various defence and international relations publications: Le Monde diplomatique, Défense et sécurité internationale (DSI), Res Militaris, Monde chinois, Conflits, La Revue de Défense nationale.

Based on the shared observation that the principles of war should retain their full relevance over a 15-year horizon, Workshop No. 5 considered how to make them operational in the light of the probable ruptures envisaged in 2035.

Workshop 4 was structured around three phases:

• a reminder of the definitions of the principles of warfare and application processes accompanied by an exchange within the group;
• a reflection around two predefined questions: on an increasingly transparent battlefield, which principles can guarantee surprise and security?
• Isn't the uncertainty principle the only principle that is permanent and timeless?

Will the types of adversaries envisaged and the porosity between the engagement environments have consequences for how the war is won in the future?

In order to answer this question, it was necessary to consider the technological environment, the geopolitical and societal context up to 2035, the likely changes in forms of adversity and their implications for understanding the principles of warfare.

Why a challenge to the principles of war? In order to answer the question posed, it was necessary to come back to the definition of a principle of war for the different participants. The following elements were quickly retained.

The discussions on the relevance of distinguishing between the principles of warfare and the principles of operations were open and rich, covering a topic of interest shared by all the participants in the group.

The workshop for foreign and French general officers was based on the following question: "The operational environment envisaged in 2035 leads us to wonder about the durability of the principles inherited from military thinkers of previous centuries. What forward-looking approaches are being adopted by Western nations to reflect on this question? ».