“The invention of gunpowder and the constant improvement of firearms are enough in themselves to show that the advance of civilization has done nothing practical to alter or deflect the impulse to destroy the enemy, which is central to the very idea of war.”
On War (1832), Book 1
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Carl von Clausewitz 68
German-Prussian soldier and military theorist 1780–1831Related quotes

Source: Woman, Church and State (1893), p. 539

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1850s

How To Defend Society Against Science (1975)

North & South Magazine http://thecivilwarhomepagediscussion2824.yuku.com/forum/getrefs/id/16744/type/0 (January 2008), Vol. 10, No. 4, p. 59
2000s

Dissertation for doctor of philosophy in christian education (May 25, 1991)

Variant translations
It is best to keep one’s own state intact; to crush the enemy’s state is only second best.
Source: The Art of War, Chapter III · Strategic Attack