(Book Jacket Status: Jacketed)
Rather than this Penguin edition, I recommend the Princeton University Press edition, translated and edited by Michael Howard and Peter Paret. That version includes very helpful essays and introductions by those two academics, as well as Bernard Brodie. Together, these three help the reader understand what Clausewitz was writing, and gently remind the reader that he should be somewhat forgiving of the author. After all, he had only just begun a major renovation of his entire work when he was felled by the cholera epidemic that struck Europe.
If you are interested in Clausewitz, READ HIM. Do not join the illiterati who quote and misquote him without ever reading On War. While it is not an easy read, the Princeton University edition is readable, and On War is the most important book on the most serious of political subjects.
This perspective is very illuminating as he discusses the political ramifications of war (war as an instrument of policy), as well as discussing the various problems that a leader in the field faces (including what he calls 'friction'). Unlike Sun Tzu, I feel that Carl's understanding may well have been deeper, and Carl's explainations are more to the point, rather than anaecdotal and poetic.
I know I sound harsh when discussing Sun Tzu. Sun Tzu was an excellent thinker, but it is Carl's work that has kept me thinking about some basic but fundamental concepts for well over a year. This book is easily worth your time. But I should warn you, this book is not for the faint of heart. The language is particularly difficult, even more difficult than that of the Art of War.
My only complaint about the book is that Carl died while it most it's chapters were still in draft!