Introduction

Abstract

Donald Rumsfeld (2002) was widely pilloried by the international media for his famous statement of a problem confronting military strategists in Afghanistan:

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 do not know. But there are also unknown unknowns, the ones we don’t know we don’t know.

However, these are words to weigh. Robert McNamara had come to the same wise realization about the war in Vietnam. Warfare is not a defined problem with a set of technical solutions. We should instead expect the unexpected.