American political columnist Meg Greenfield (1930-1999) wrote in the Washington (DC) Post on February 5, 1996:
 
“Ninety percent of politics is deciding whom to blame. The other 10 percent may be labeled miscellaneous. Once in a blue moon, it is true, a person or cause will come along that is capable of inspiring more than that, submerging the scapegoating instincts in more positive feelings of excitement and hopefulness. But as a rule it doesn’t work that way. Blame is the indispensable motivator, a kind of political first cause from which everything else flows.”
 
“Ninety percent of politics is deciding whom to blame” has become a popular political quotation.
 
 
Wikipedia: Meg Greenfield
Mary Ellen (Meg) Greenfield (December 27, 1930 – May 13, 1999) was a Washington Post and Newsweek editorial writer and a Washington, D.C., insider known for her wit.
 
5 February 1996, Washington (DC) Post, “Back to Class War?” by Meg Greenfield, pg. A21, col. 1:
Ninety percent of politics is deciding whom to blame. The other 10 percent may be labeled miscellaneous. Once in a blue moon, it is true, a person or cause will come along that is capable of inspiring more than that, submerging the scapegoating instincts in more positive feelings of excitement and hopefulness. But as a rule it doesn’t work that way. Blame is the indispensable motivator, a kind of political first cause from which everything else flows. What is striking about the present moment in our national politics is that there looks to be the beginning of a new blame era.
       
Google Books
Newsweek
Volume 127, Issues 2-13
12 February 1996
Pg. 340:
THE LAST WORD
NINETY PERCENT OF POLITICS IS DECIDING WHOM to blame. The other 10 percent may be labeled miscellaneous.
   
Google Books
The Book of Percentages:
Over 500 bizarre, obscure, random, and surprisingly enlightening facts about just about everything
By Tom Philbin
Avon, MA: Adams Media
2009
Pg. ?:
“90% of politics is deciding whom to blame.”
Meg Greenfield, U.S. journalist
 
Google Books
Blaming Europe?:
Responsibility Without Accountability in the European Union
By Sara B. Hobolt and James Tilley
New York, NY: Oxford University Press
2014
Pg. 8:
‘Ninety percent of politics is deciding whom to blame.’
Meg Greenfield, Newsweek, 12 February 1996  
 
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Joan Kramer‏
@JoanKramer32
Ninety percent of politics is deciding whom to blame…. #MegGreenfield #aphorism
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