The US Was Defeated In #Vietnam By Systematic Theory Of Mind Error

The US had vast superiority in all assets that were thought to matter but was still defeated in the Vietnam War — why?

It is clear that the US possessed much more in the way of conventional military assets in the conflict with North Vietnam than the opposing forces.  This point is widely accepted so I will not spend much time arguing for it.  For example, the US had tanks while the Viet Cong had no anti-tank weapons.*  US forces had “superb artillery and air support” (Sheehan, p. 447, 1988) which enabled any US troops facing locally superior odds to succeed.  The entire US army fought with the doctrine of “superior firepower” (Sheehan, p. 243, 1988).  The financial resources that the US was able to apply also hugely outweighed those of its opponents in a largely peasant guerrilla army.  Sheehan (p. 624, 1988) writes that commodity aid to South Vietnam reached the staggering figure of $650m in 1966.

This last point is decisive.  It has been wisely observed that:

“Most wars have been wars of attrition, settled by which side had more staying power through the ability to apply men and materiel.” **

The GDP of North Vietnam in 1965 was $6.0bn in 2015 dollars.  The GDP of the US in 1965 was $4.1tn in 2009 dollars — that is, 683x larger.

So why did the US lose?  Consider the following highly insightful quotation.

“When McNamara wants to know what Ho Chi Minh is thinking, he interviews himself.” ***

Robert McNamara was the Secretary of Defense at the time, and so crucial to  managing the war effort.  It is clearly important to know what the enemy is thinking.  McNamara’s error was to do this in the way that most people do.  This is where we come to Theory of Mind.

Theory of Mind is the label in psychology for the way we predict and explain the behaviour of others.  We all do this all the time.  There is a vibrant debate in psychology as to how we do it.  The mainstream view is called “Theory Theory.” This holds that children as young as five, who already have a serviceable Theory of Mind, have formed it by learning a theory of other people.  They are supposed to have done this by most psychologists in a scientific fashion: they propose hypotheses and then confirm or disconfirm them empirically.

I support the opposing view, which is known as Simulation Theory.**** This suggests that we run our Theory of Mind by putting ourselves in the position of others and seeing what we would do.  This, according to the quotations, is exactly what McNamara did.  And it is why he was wrong and why the US lost.

We can see this same factor in action with another quote from a significant protagonist in Vietnam: Green Beret Colonel Kurtz who makes the following  observation on realising that the Viet Cong have removed the arms of all the children in a village who were vaccinated against Polio by US forces.

And then I realized… like I was shot… like I was shot with a diamond… a diamond bullet right through my forehead. And I thought, my God… the genius of that! The genius! The will to do that!

The surprise of the Colonel is again an illustration of Theory of Mind error.  If his simulation of the Viet Song had been more accurate, he would have been able to predict their action here.  That he was not, and that he was able to see how effective, if inhuman, this strategy was, shows that he was perhaps able to adjust and improve his Theory of Mind more than McNamara was.

It also illustrates the type of Theory of Mind error we should expect.  McNamara was a company man, who was experienced from his time running Ford in systems analysis and data handling.  So when he simulated Ho Chi Minh, he would draw conclusions along the lines of “I am faced with overwhelming odds; all of the analysis says that overwhelming odds always win; I therefore cannot win.”

What this misses out is the “Blut und Boden” point hinted at by Kurtz.  It misses out the will to fight on one’s own soil irrespective of the prospects of success.  It misses out the will to enlist the entire male and female population in the war effort, with many women driving supplies down the Ho Chi Minh trail at night without lights under largely ineffective yet heavy US bombing.  It misses out what the French missed at Dien Bien Phu: the will to disassemble artillery pieces and carry them up jungled mountains by hand.

So this is why the US lost.  It is also presumably why my book is held by the following library:

Institute for Defense Analyses Library
IDA Library

Alexandria, VA 22311 United States

You can also buy a copy at the link below if you want to know more about Theory of Mind. ****

* Sheehan, N. (1988)   A Bright Shining Lie: John Paul Vann and America in Vietnam.  Vintage Books

** “The other side has a vote”, The Economist, Oct 14 2017

***  This quotation is from James Willbanks, an army strategist.  It is written up in The Economist, “Buried Ordnance,” in the issue of Sep 14 2017.  The piece is a review of “The Vietnam War,” a TV documentary by Burns and Novick.

**** Short, T L 2015  Simulation Theory: a Psychological and Philosophical Consideration.  Abingdon: Routledge.  URL: