“O’Sullivan’s First Law: An eternal truth” by John O’Sullivan, published in the National Review on October 27, 1989, stated:
 
“All organizations that are not actually right-wing will over time become left-wing.”
 
The political “law” is often called “O’Sullivan’s Law” and is often stated as “anything that is not actively conservative every day will eventually become liberal.”
 
 
Wikipedia: John O’Sullivan (columnist)
John O’Sullivan, CBE (born April 25, 1942) is a British conservative political commentator and journalist and currently vice president and executive editor of Radio Free Europe/Radio Liberty.[1][2] During the 1980s, he was a senior policywriter and speechwriter in 10 Downing Street for Margaret Thatcher when she was British prime minister and remained close to her up to her death. He is also a Member of the Board of Advisors for the Global Panel Foundation, a respected NGO that works behind the scenes in crisis areas around the world.
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“O’Sullivan’s First Law”
He is known for O’Sullivan’s First Law (O’Sullivan’s Law): “All organizations that are not actually right-wing will over time become left-wing.”
 
Free Republic
June 26, 2003, 1:45 p.m.
O’Sullivan’s First Law
An eternal truth.
By John O’Sullivan
EDITOR’S NOTE: This appeared in the October 27, 1989, issue of National Review.
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That is explained by O’Sullivan’s First Law: All organizations that are not actually right-wing will over time become left-wing. I cite as supporting evidence the ACLU, the Ford Foundation, and the Episcopal Church. The reason is, of course, that people who staff such bodies tend to be the sort who don’t like private profit, business, making money, the current organization of society, and, by extension, the Western world. At which point Michels’s Iron Law of Oligarchy takes over — and the rest follows.
 
Google Books
Backward and Upward:
The New Conservative Writing
By David Brooks
New York, NY: Vintage Books
1996
Pg. XIV:
National Review editor John O’Sullivan posited “O’Sullivan’s Law”: that any institution that is not explicitly conservative turns liberal over time.
 
Urban Dictionary
O’Sullivan’s Law
O’Sullivan’s Law states that any organization or enterprise that is not expressly right wing will become left wing over time. The law is named after British journalist John O’Sullivan.
 
Television shows are the best examples of this. 24, House. Charitable foundations are worse but harder to see.
 
One of the reasons for this is leftist intolerance versus right-wing tolerance. Right wingers are willing to hire openly left-wing employees in the interest of fairness. Left-wingers, utterly intolerant, will not allow a non-Liberal near them, and will harass them at every opportunity. The result over time is that conservative enterprises are infiltrated by leftists but leftist enterprises remain the same or get worse.
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by Melvin Udall April 22, 2011
     
Power Line
POSTED ON FEBRUARY 3, 2012 BY STEVEN HAYWARD IN LIBERALS
O’SULLIVAN’S FIRST LAW IN ACTION
O’Sullivan’s First Law, named for John O’Sullivan, former editor of National Review, speechwriter for Margaret Thatcher, and author of the fine book The President, The Pope, and the Prime Minister, goes as follows: Any institution that is not explicitly right wing will become left wing over time.  Good example include such seemingly anodyne institutions like the League of Women Voters, PTAs, National Public Radio, most professional associations like the American Bar Association, the Pew Charitable Trust (which actually was intended to be explicitly conservative, and still got captured by the left), and so forth.  This week is seeing a good example of the logic and action of O’Sullivan’s First Law at work.
 
RushLimbaugh.com
What Happened to John Boehner?
January 13, 2015
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RUSH:  Well, yeah, but I don’t think that’s the explanation.  It happens to too many people up there.  Once again, let me cite for you O’Sullivan’s Law:  Anything that is not actively conservative every day will eventually become liberal.  Boehner was a ranking leader in Mr. Newt’s leadership.  I mean, that was as pedal-to-the-metal conservative as you can get.  And then, I mean, let’s face it, the budget battle of 1995 just destroyed a bunch of these guys, David.  It just destroyed ‘em.  And conservatism is constantly under attack, and one by one, the leadership in Newt’s group began to fall away, one by one.  I think they got bit by what the dominant culture, political and social, in Washington is.