This essay explores notions of knowledge and intelligence in war, with a particular emphasis on knowledge about knowledge. It is argued that such second order knowledge deserves more attention in military training and education, especially in the context of maneuver warfare. More precisely, information operations within the maneuver warfare paradigm largely aim to present or withhold (second order) knowledge to the enemy in order to gain an advantage. This is elaborated using cultural and historical examples. Furthermore, the relevance of flaws and biases in human cognition and decision-making in war are discussed. In particular, it is argued that while tactical decision-making can be much improved upon through training and exercises, it is more difficult to train experts in strategic decision-making. The article is concluded with some reflections and recommendations for how to improve military training and education.