“War doesn’t determine who’s right, only who’s left” is a popular anti-war slogan, cited in print from at least 1932-1933. The saying is often credited to philosopher Bertrand Russell (1872-1970), but there is no documented evidence that he ever said it.
 
“War does not determine who is right — only who is left. — Montreal Star” was cited in the February 1932 The Reader’s Digest magazine. A February 24, 1932 article in the Greensboro (NC) Daily News about a Rotary meeting reported, “‘The next war will not decide who is right but who is left,’ Col. Frank P. Hopgood declared.”
 
An April 1932 citation credits the saying to Jessie Woodrow Wilson Sayre, the daughter of U.S. Presdient Woodrow Wilson (1856-1924) and the wife of Harvard Law School professor and U.S. Assistant Secretary of State Francis Bowes Sayre, Sr. (1885-1972).
 
[This entry was prepared with research assistance by the Quote Investigator.]
   
     
25 February 1915, Xenia (OH) Daily Gazette, “Bits of Byplay” by Luke McLuke (Cincinnati Enquirer), pg. 7, col. 5:
Betcha!
We think this thought is rather bright,
And not of wit bereft.
You’ll find the fellow who is right
Is mighty seldom left.
 
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February 1932, The Reader’s Digest, pg. 108, col. 2:
War does not determine who is right — only who is left. — Montreal Star.
 
24 February 1932, Greensboro (NC) Daily News, pg. 16, col. 1:
Horrors of Next War
Pictured By Hobgood
In Talks to Rotarians
It Will Not Be Fought Against Armed Forces But Against Civilians And “Will Not Decide Who Is Right But Who Is Left,” He Asserts—27th Birthday of Rotary Is Observed With Talk By Luther H. Hodges.
“The next war will not decide who is right but who is left,” Col. Frank P. Hobgood declared in a stirring appeal for disarmament before 250 Rotarians and Rotary Anns assembled in a combined Rotary inter-city meeting and birthday party at the ballroom of the King Cotton hotel last night.
 
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The Christian Leader
Volume 35, Part 2
30 April 1932
Pg. 572:
“You do not drift into peace, you drift into war,” said Mrs. Sayre. And after all, “force does not prove who is right; only who is left.”
(Jessie Woodrow Wilson Sayre’s speech was titled “Our Relationship to Peace in the World.”—ed.)
 
28 June 1932, El Paso (TX) Herald-Post, pg. 4, col. 2:
“War does not determine who is right—only who is left,” a reader writes: “In the World war, the United States is left—holding the bag.”
 
12 November 1933, Springfield (MA) Republican, “Antiwar placard seied by police at Northampton,” pg. 19A, col. 7:
...“War does not prove who is right—only who is left.”
   
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The Treasury of Modern Humor
By Martha Lupton
Indianapolis, IN: M. Droke
1938
Pg. 80:
War
— boiling point of greed.
—business in which there are too many ghosts and not enough glory.
—daft, draft, graft.
—doesn’t determine who is right — only who is left.
   
3 April 1939, Augusta (GA) Chronicle, pg. A6, col. 4: 
War determines not who is right, but who is left.
 
29 July 1939, Daily Freeman (Kingston, Jamaica), “Office Cat” by Junius, pg. 5, col. 4:
Reckless driving never determines who is right, but who is left.
 
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18 July 1941, St. Petersburg (FL) Evening Independent, “Free Speeches” by Lee Morris, pg. 6, col. 3:
Today a good many people seem to think that war settles who’s right. My personal opinion is that the only thing it settles is who’s left.
 
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1 October 1946, Miami (FL) Daily News, pg. 12A, col. 1:
There are dangers both of underestimating and overestimating that verdict. Because it was more or less expected, because of the cynics version that “wars prove not who’s right but who’s left,” and because it represents a departure in international law, many may discount it.
 
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December 1946, The Rotarian. pg. 64, col. 1:
THE ATOM BOMB, some grim wit has said, will never determine who is right—only who is left.
 
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3 January 1949, Spokane (WA) Daily Chronicle, “Johnston Says World in Fretful Armistice” by Eric Johnston, pg. 1, col. 1:
Certainly, sane men reject war as an answer. War solves nothing and might annihilate everything. War doesn’t prove who’s right but who’s left.
 
16 June 1957, Seattle (WA) Daily Times, “Daffynitions” by Paul H. Gilbert, Sunday Supplement, pg. 12, col. 4:
WAR: A conflict that doesn’t determine who’s right—only who’s left.
 
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The Quotable Intellectual:
1,417 bon mots, ripostes, and witticisms for aspiring academics, armchair philosophers—and anyone else who wants to sound really smart
By Peter Archer
Avon, MA: Adams Media
2010
Pg. 100:
“War does not determine who is right—only who is left.” — Bertrand Russell