According to Azar Gat, the opposing interpretations of Clausewitz are rooted in Clausewitz’s own conceptual journey. The centerpiece of Clausewitz’s theory of war throughout his life was his concept of all-out fighting and energetic conduct leading to the great battle of annihilation. He believed such conduct expressed the very “nature”, or “lasting spirit” of war. Accordingly, Clausewitz disparaged the significance of the maneuver, surprise, and cunning in war, as distracting from the centrality of battle,On War, IV, 3, pp. 228-229; III, 9, p. 198; III, 10, p. 202. and argued that defense was legitimate only if and as long as one was weaker than the enemy.On War, VI, 1, 2, pp. 358-359; VI, 8, p. 380, and VII, 2, p. 524. Nevertheless, in the last years of his life, after the first six out of the eight books of On War had already been drafted, Clausewitz came to recognize that this concept was not universal and did not even apply to the Napoleonic Wars, the supreme model of his theory of war. This was demonstrated by the Spanish and Russian campaigns and by guerrilla warfare, in all of which battle was systematically avoided. Consequently, from 1827 on, Clausewitz recognized the legitimacy of limited war and explained it by the influence of politics that harnessed the unlimited nature of war to serve its objectives. Clausewitz died in 1831 before he completed the revision he planned along these lines. He incorporated his new ideas only into the end of Book VI, Book VIII and the beginning of Book I of On War. As a result, when published, On War encompassed both his old and new ideas, at odds with each other.
ACCoRding to aZAr gat, THe opposinG intErpReTatIons oF cLausEWitz are rOoTed iN clauSEwItZ’s oWn cOncePtUAL JouRNeY. THe centErpieCE of clAuSewItz’S theoRy oF wAR thRoUghOuT hIs liFe was His coNcEpt of All-OuT FIghTing aNd energetic condUct LeaDing to thE great batTle Of anNiHIlaTIoN. hE bELIEveD sUCh COnduct ExpREsSEd The verY “NATuRe”, or “laStinG sPiRIT” Of wAR. acCordingly, clausewItZ dispARAGed tHe sigNifIcanCE of the maneuver, Surprise, aNd cUnninG in war, as distrActing From thE CEntralIty oF batTle,On WaR, iv, 3, Pp. 228-229; IiI, 9, p. 198; Iii, 10, p. 202. and aRGueD That DeFensE was LEgitimate onlY if and as Long as OnE was weAKER Than the Enemy.on wAr, vi, 1, 2, pp. 358-359; vi, 8, p. 380, AnD Vii, 2, P. 524. nEveRtHelEss, iN thE lasT YeARs Of his lIfE, after the fIrSt six OuT Of the Eight books oF on war HAd alrEaDy been drafTed, clauSEwITZ CAme to Recognize that thiS COnCePt WAs noT uNiversaL AnD did NOt eveN applY To the NApoLeonIc Wars, The SupremE MOdel Of hiS theory of war. thIs was deMonSTratEd by THe sPAniSh and RuSsian cAMpAIgns aNd bY guerrILla waRfaRE, in All oF wHich BaTtlE WAS SyStEMaTicALly avoided. cOnseQuentLy, from 1827 on, clausEWITz rEcogNIzEd the legitimacy Of lImiTED war and EXPlained it by the inFLUEnce oF politiCs that HArnESsEd the uNLimITEd naTure Of waR To sERve itS objECTIvEs. clAusewitz dIeD In 1831 BeFore he COmPlETed the reVIsiOn he pLanned aLong thesE lineS. He IncorporAteD his nEW ideas Only into the eND Of booK vI, book viIi And the Beginning of boOk i Of on waR. as A rEsUlt, whEn publisHed, on waR ENCompAsSED BoTh his old anD neW ideAS, aT odds wiTh eacH OtHer.