Donald Rumsfeld - Known and Unknown: A Memoir

PART I
Lessons in Terror

PART II
An American, Chicago Born

PART III
The U.S. Congress: From Camelot to Quagmire

PART IV
In Nixons Arena

PART V
Javelin Catcher: Inside the Ford White House

PART VI
Fighting the Cold War

PART VII
Back to Reality

PART VIII
Leaning Forward

PART IX
Into the Graveyard of Empires

PART X
Saddams Miscalculation

PART XI
The Occupation of Iraq

PART XII
Wartime Detention

PART XIII
Pulling On Our Boots: Challenges and Controversies Beyond the War Zones

PART XIV
The Long, Hard Slog

A n internet search of known unknown in the autumn of 2010 resulted in more than three hundred thousand entries, a quarter million of which were linked to my name. There is an entry on Wikipedia. The reference has been turned into poetry. That poetry has been set to music. And that was just on the first page of the search results.

Yet for a phrase seemingly so well known, there is some irony in the fact that its origins and meaning remain largely unknown.

The phrase first became publicly linked to me in early 2002. Toward the end of one of my Pentagon press briefings, a journalist told me that reports were suggesting the absence of a link between Saddam Husseins regime and terrorists seeking weapons of mass destruction. These unidentified reports, the questioner suggested, were evidence of a lack of a direct link.

Putting aside the substance of the reporters questionat least for the momentI raised a larger point about the limits of human knowledge. I responded:

Reports that say something hasnt happened are always interesting to me because as we know, there are known knowns: there are things we know we know. We also know there are known unknowns: that is to say we know there are some things [we know] we do not know. But there are also unknown unknownsthe ones we dont know we dont know. And if one looks throughout the history of our country and other free countries, it is the latter category that tends to be the difficult one.

At first glance, the logic may seem obscure. But behind the enigmatic language is a simple truth about knowledge: There are many things of which we are completely unawarein fact, there are things of which we are so unaware, we dont even know we are unaware of them.

Known knowns are facts, rules, and laws that we know with certainty. We know, for example, that gravity is what makes an object fall to the ground.

Known unknowns are gaps in our knowledge, but they are gaps that we know exist. We know, for example, that we dont know the exact extent of Irans nuclear weapons program. If we ask the right questions we can potentially fill this gap in our knowledge, eventually making it a known known.

The category of unknown unknowns is the most difficult to grasp. They are gaps in our knowledge, but gaps that we dont know exist. Genuine surprises tend to arise out of this category. Nineteen hijackers using commercial airliners as guided missiles to incinerate three thousand men, women, and children was perhaps the most horrific single unknown unknown America has experienced.

I first heard a variant of the phrase known unknowns in a discussion with former NASA administrator William R. Graham, when we served together on the Ballistic Missile Threat Commission in the late 1990s. Members of our bipartisan commission were concerned that some briefers from the U.S. intelligence community treated the fact that they lacked information about a possible activity to infer that the activity had not happened and would not. In other words, if something could not be proven to be true, then it could be assumed not to be true. This led to misjudgments about the ballistic missile capabilities of other nations, which in some cases proved to be more advanced than previously thought.

The idea of known and unknown unknowns recognizes that the information those in positions of responsibility in government, as well as in other human endeavors, have at their disposal is almost always incomplete. It emphasizes the importance of intellectual humility, a valuable attribute in decision making and in formulating strategy. It is difficult to acceptto knowthat there may be important unknowns. The best strategists try to imagine and consider the possible, even if it seems unlikely. They are then more likely to be prepared and agile enough to adjust course if and when new and surprising information requires itwhen things that were previously unknown become known.

I also encountered this concept in Thomas Schellings foreword to Roberta Wohlstetters book Pearl Harbor: Warning and Decision, in which Schelling identified a poverty of expectations as the primary explanation for Americas inability to anticipate and thwart the Japanese attack on Hawaii. This has been interpreted to mean that the beginning of wisdom is the realization of how little one truly knows.