18 Irregular warfare
Guerrillas, insurgents and terrorists
Introduction: two kinds of warfare
It is both useful and historically justifiable to divide the experience of warfare into two
broad categories: regular and irregular. The former is warfare between the regular, armed
forces of states, while the latter is warfare between those forces and the irregular armed
forces of non-state political entities. Irregular warfare is asymmetrical: the opponents
are certain to be very different. Also, the warfare may well be transcultural. It follows
that such belligerency must pose unusual, and unusually severe, challenges to the regular
side. An army justly proud of its military effectiveness in regular warfare is apt to
discover that irregular combat, with the absence of large-scale open combat, prices its
strength at a heavy discount. To be outstanding at regular warfare does not mean that one
will even be competent, let alone good, at warfare of an irregular kind. To employ a vital
Clausewitzian concept, the ‘grammar’ of irregular warfare is radically different from that
of regular warfare (Clausewitz, 1976: 605).
Thus far in this book, only in Chapter 17 did irregular warfare assume centre-stage.
The reason for the apparent neglect of such warfare through most of these pages is that it
has not played a sufficiently significant role in the master narrative of strategic history to
warrant being accommodated in an already substantial text. To explain: over the past two
centuries, irregular warfare has been widespread, frequent and typically extremely bloody;
however, until recent years such warfare, in its several variants, has never been the
dominant category of politically organized violence in the mainstream of strategic history.
Only in the twenty-first century, following 9/11, has the principal plot line of world
strategic history privileged irregular warfare. Never before in those 200 years have the
major powers elevated irregular hostilities to the status of the main strategic activity of
the era. This condition may not long endure. There could be a return to dominant signifi-
cance of the plausible threat of regular warfare between states, including major powers.
But, for the present at least, irregular warfare is the cutting edge of strategic history.