Joint warfighters are expected to have at least a basic familiarity with the Principles of War. These principles "guide warfighting at the strategic, operational, and tactical levels," Joint Publication 3-0: Doctrine for Joint Operations tells us, "They are the enduring bedrock of U.S. military doctrine." Ten years ago the Strategic Studies Institute published a monograph— The Principles of War in the 21st Century , written by William T. Johnsen and several co-authors—that neatly summarizes the understanding of the principles of war. The principles are an "intellectual framework" that "shapes" the professional soldier's "thought processes," Johnsen and his co-authors state. The warfighter should possess a "comprehensive understanding of the principles" so that he can "expand creatively upon them" as well as decide which are relevant to circumstance, and which are not. Thus conventional thinking would have us believe that the principles of war, rooted in experience and validated by their pivotal station in the formulation of joint doctrine and professional military education, are vital to efficient war planning and effective command.