“If religions are diseases of the human psyche, as the philosopher Grintholde asserts, then religious wars must be reckoned the resultant sores and cankers infecting the aggregate corpus of the human race. Of all wars, these are the most detestable, since they are waged for no tangible gain, but only to impose a set of arbitrary credos upon another’s mind.”

V. E. Day proclamation (8 May 1945) http://www.jah-rastafari.com/selassie-words/show-jah-word.asp?word_id=declar_ve.
Context: May it be taken as Divine significance, that, as We mark the passing of the Nazi Reich, in America at San Francisco, delegates from all United Nations, among whose number Ethiopia stands, are now met together for their long-planned conference to lay foundations for an international pact to banish war and to maintain World Peace. Our Churches pray for the successful triumph of this conference. Without success in this, the Victory, We celebrate today, the suffering that We have all endured will be of no avail.
To win the War, to overcome the enemy upon the fields cannot alone ensure the Victory in Peace. The cause of War must be removed. Each Nation's rights must be secure from violation. Above all, from the human mind must be erased all thoughts of War as a solution. Then and then only will War cease.

Socialism (1922), Epilogue (1947)
Context: When people were committed to the idea that in the field of religion only one plan must be adopted, bloody wars resulted. With the acknowledgment of the principle of religious freedom these wars ceased. The market economy safeguards peaceful economic co-operation because it does not use force upon the economic plans of the citizens. If one master plan is to be substituted for the plans of each citizen, endless fighting must emerge. Those who disagree with the dictator's plan have no other means to carry on than to defeat the despot by force of arms.

Source: Extremely Loud and Incredibly Close (2005), p. 99

24 March 1999 on German television, quoted in the documentary film ‘Es begann mit einer Lüge’, the complete manuscript of the film http://www.ag-friedensforschung.de/themen/NATO-Krieg/ard-sendung.html
Context: We don't wage war, but we are called upon to impose a peaceful solution in Kosovo by military means as well.

Non combattete mai con la religione, né con le cose che pare che dependono da Dio; perché questo obietto ha troppa forza nella mente degli sciocchi.
Number 253.
Counsels and Reflections (1857)

1900s, The Moral Equivalent of War (1906)
Context: The war-party is assuredly right in affirming and reaffirming that the martial virtues, although originally gained by the race through war, are absolute and permanent human goods. Patriotic pride and ambition in their military form are, after all, only specifications of a more general competitive passion. They are its first form, but that is no reason for supposing them to be its last form. Men are now proud of belonging to a conquering nation, and without a murmur they lay down their persons and their wealth, if by so doing they may fend off subjection. But who can be sure that other aspects of one's country may not, with time and education and suggestion enough, come to be regarded with similarly effective feelings of pride and shame? Why should men not some day feel that is it worth a blood-tax to belong to a collectivity superior in any respect? Why should they not blush with indignant shame if the community that owns them is vile in any way whatsoever? Individuals, daily more numerous, now feel this civic passion. It is only a question of blowing on the spark until the whole population gets incandescent, and on the ruins of the old morals of military honor, a stable system of morals of civic honor builds itself up. What the whole community comes to believe in grasps the individual as in a vise. The war-function has grasped us so far; but the constructive interests may some day seem no less imperative, and impose on the individual a hardly lighter burden.

Source: 1790s, The Age of Reason, Part II (1795), Chapter III: Conclusion.

Source: Autobiography of Mark Twain, Vol. 3 (2015), p. 136, of President Theodore Roosevelt