Carl Philipp Gottfried von Clausewitz died almost 200 years ago, yet he remains one of the most important and influential of all military thinkers. His teachings combined strategy with military knowledge to produce a dialectic approach to the philosophy of warfare, and his work is still widely taught in military academies around the world. There are few senior military leaders anywhere who are not familiar with his seminal book, On War.

In fact, with the exception of Napoleon Bonaparte, no man was more influential on the military tactics and strategy of 19th century warfare than Clausewitz, a Prussian soldier and military theorist who stressed the moral and political aspects of war. On War was mandatory for all military students and officers to read during the 19th century, and it was common practice for generals during the American Civil War to carry Clausewitz’s treatise and read it to assist them in strategy and tactics. On War covered every conceivable facet of warfare, using historical battles as examples of what to do and what not to do. The treatise discusses how opposite forces interact, and how unexpected new developments unfolding under the "fog of war" called for rapid decisions by alert commanders. In opposition to Antoine-Henri Jomini, he argued war could not be quantified or graphed or reduced to mapwork and graphs.

Few men were more influential on the military tactics and strategy of 19th century warfare than Antoine-Henri Jomini, and yet the introduction for a 1947 English translation of Jomini’s Art of War noted, “The military world that today burns gun-powder at the altar of Clausewitzian doctrine has all but forgotten Antoine-Henri Jomini.” The author of that introduction, Lt. Col. J.D. Little of the US Marine Corps, was right then, and he remains correct today - while Clausewitz’s aphorisms are still used to support everything from military action to business management, the work of his contemporary writer Jomini has been all but forgotten.

During the Napoleonic Era and throughout the 19th century, however, the situation was very different. Jomini was regarded as the preeminent strategist and writer of his generation, while Clausewitz was virtually unknown outside the General Staff of the Prussian Army. In the intervening period, Clausewitz has come to be regarded as the most important writer and strategic analyst of the period, whereas the writings of Jomini have been discarded and largely ignored. As a result, many military historians and strategists have only recently begun to understand how important Jomini was and how relevant his writings remain today.

In lamenting what had happened to Jomini’s reputation, Little asserted, “No man in the history of war has exerted a greater influence on the development of modern warfare than Napoleon Bonaparte. No man has been more responsible for Napoleon’s influence as Antoine-Henri Jomini.” Again, Little had a point, because unlike Clausewitz, the writings of Jomini had a direct influence on the conduct of wars during the 19th century. While Clausewitz was not widely read outside Prussia (and later Germany) until the final years of the 19th century, few generals in Europe and America were unfamiliar with Jomini’s works, and many used his Summary of the Art of War as their main guide to strategy and tactics.

Why is it that Jomini has been forgotten while Clausewitz’s name is now far more famous than it ever was during his lifetime? One of the reasons is that Clausewitz attempted to develop a philosophy of war that went well beyond the mechanics of combat. Such a philosophy is timeless precisely because it is not linked to the tactics or weapons of a particular period. This is made evident by the fact that as recently as the First Gulf War (1990–1991), senior military leaders in the coalition against Iraq were quoting Clausewitz.