Search tips
Search criteria 


Logo of jrsocmedLink to Publisher's site
J R Soc Med. 2007 February; 100(2): 63–64.
PMCID: PMC1790982

Overconfidence in warfare

Lord David Owen's analysis of hubris and nemesis in heads of government (JRSM November 2006)1 is a valid and useful set of medical insights into a topic of literally life and death importance. But we also need to ask why overconfident men—and it is mainly men—rise to power so often, and yet also then make so many political and military blunders.2

Evolutionary psychology is the effort to identify those universal human behaviours that adapted us to the environment in which we evolved—primarily a world of small competing clans of hunters and gatherers.3 In such a world, where conflict was frequent (in preliterate societies, adult mortality from warfare is rarely less than 10% and can rise to 50% or more4) overconfidence could have been adaptive. The ability to bluff an enemy into submission and genuine optimism in the face of heavy adverse odds may well have been promoted by natural selection.5 In Iraq, Bush and Hussein both showed a similar lack of reality (Hussein was convinced the Americans would never invade and that if they did his forces would win, while Bush is quoted as ‘relentlessly optimistic’ and convinced the postwar occupation ‘would resemble the American liberation of Germany and Japan’).6

Democracies need to be led by intelligent, curious, analytical, and cautious leaders of either sex. Unfortunately, our political systems (and especially the US system of primaries to select presidential candidates) tend to select overconfident men. The first step in overcoming this danger is correct diagnosis, and the JRSM is to be congratulated on beginning this process.


Competing interests None declared.


1. Owen D. Hubris and Nemesis in Heads of Government. J R Soc Med 2006;99: 548-51 [PMC free article] [PubMed]
2. McNamara R. Blundering Into Disaster: Surviving the First Century of the Nuclear Age. New York: Pantheon Books, 1986
3. Buss DM, ed. The Handbook of Evolutionary Psychology. New York: John Wiley, 2005
4. Keeley LH. War before Civilization: The Myth of the Peaceful, Noble Savage. Oxford: Oxford University Press, 1996
5. Johnson DDP, Wrangham, RW, Rosen SP. Is military incompetence adaptive? An empirical test with risk-taking behavior in modern warfare. Evolution Hum Behav 2002;23: 245-64
6. Johnson DDP. Overconfidence and War: The Havoc and Glory of Positive Illusions. Cambridge, Mass: Harvard University Press, 2004

Articles from Journal of the Royal Society of Medicine are provided here courtesy of Royal Society of Medicine Press