Understanding International Relations, Third Edition

War in the twentieth century
In the nineteenth century, the view that war was a legitimate act of state was
broadly accepted by international lawyers as a concomitant to the doctrine
of sovereignty. So long as the war-making body had the authority to act,
and followed the correct legal procedures (a proper declaration of war, for
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example), war could be waged lawfully, and without any legal interest in the
reasons for this act of state. This is no longer the case. The Covenant of the
League of Nations of 1919, the Pact of Paris of 1928, the United Nations
Charter of 1945 and the London Charter of the same year – which estab-
lished the War Crimes Tribunal that sat at Nuremberg – taken together have
established a new legal regime in which war is only legitimate in two cir-
cumstances, as an act of self-defence, or as a an act of law enforcement to
assist others in defending themselves. Not only is this the current legal posi-
tion; it also seems to correspond to the ways in which most people thought
about war in the twentieth century, namely as a disaster that should be
avoided at almost all costs – indeed, the current law on war is more likely
to be criticized for being too permissive than for restricting the activity too
closely. Both morally and legally, a Clausewitzian view of war seems today
to be unacceptable.
Of course, from a realist point of view, all this is by the by. If states still
make war on Clausewitzian lines, then the fact that law and public opinion
goes against them is neither here nor there. At best it explains some of the
peculiarities of modern war, in particular the unwillingness to call a spade
a spade – hence the British Government always refers to the South Atlantic
Conflict of 1982 rather than the Falklands War, the problems involved in
fighting a declared war being too complicated to contemplate. But do states
still make war as a rational act of policy? Some try to, sometimes – but on
the whole, twentieth-century conditions worked against war being fought
in terms of Clausewitzian calculations. There are two points here, one
about the actual calculations, the other about the role of calculations in
decisions for war.
The first point is simple; in the twentieth century the costs of war rose
dramatically, while the benefits either remained the same or, more often,
fell. As mentioned in Chapter 1 above, Norman Angell saw this in the years
before 1914 and it has become even truer post-1945. The rise in destruc-
tiveness of war has been exponential – from the mayhem of machine guns,
breechloading artillery and barbed wire in the First World War, to the
strategic bombing of the Second to the threat of nuclear annihilation of
a potential Third World War. The economic structures of society are destroyed
by war, financial resources dissipated, political stability undermined. The
benefits of success have not risen in the same way; in material terms the
rewards for a successful war are now less significant than they once were.
National wealth does not, on the whole, come from the conquest of terri-
tory or the cornering of raw materials – although, as the invasion of Kuwait
in 1990 suggests, there may still be, in some circumstances, possibilities
here. A successful war may remove an enemy or competitor, and there may
be circumstances in which this is a very worthwhile result – but on the
whole one would expect far fewer wars to emerge from rational calculation
The Balance of Power and War
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in the twentieth century than in the nineteenth. Yet the former was a century
of warfare, by most statistical indices more war-prone than the latter, which
suggests that war is no longer fought as a rational act, but for some other
reason.
A clue to this other reason comes when we examine the fate of Clausewitz’s
triad under modern conditions. The people, the army and the government
are supposed to have one function each which fits in with the other two –
the raw feelings of the people are harnessed to political ends by the govern-
ment which are then translated into action by the military. This can still
work, but only rarely. Returning to an earlier example, the North Vietnamese
were remarkably Clausewitzian in their approach to the Vietnam War, not
altogether surprisingly since their ideological influences – Marx, Engels,
Lenin and Mao – were all avid readers of Clausewitz. The North Vietnamese
people were mobilized behind the war, but not allowed a say in its execu-
tion. The political leadership held tight control over the objectives of the
war, and the army was given freedom of action only in its proper sphere of
operation. By contrast, the US army was given no clear objectives in
Vietnam. The US president interfered with military operations, to the point
of actually choosing bombing targets from the White House briefing rooms.
The US public was never mobilized behind the war effort, and, via the
media and Congress, set political constraints on the war which were
detailed, inconsistent and deeply harmful to the development of a coherent
strategy.
The key point here is that this latter state of affairs is far more common
than the Clausewitzian purity of the North Vietnamese. North Vietnam, the
Prussia of South east Asia, recreated a Clausewitzian environment by having
nationalism without democracy, and a state strong enough to control the
army and not to be constrained by informal expressions of popular opinion.
This is a very unusual combination. In the advanced industrial countries
public opinion and democratic institutions mean that ‘the people’ are hard
to mobilize, and, once mobilized, will refuse to play their designated role as
cheerleaders of the government and army – they insist on playing a major
role in determining goals and approving (or more likely disapproving)
strategies and tactics. Congressional and Parliamentary investigations in the
US and UK into the reasons for and intelligence concerning the 2003 Iraq
War, as well as in-depth and often critical media coverage of the conflict,
have infuriated the governments concerned, but such questioning is, nowa-
days, more or less inevitable – and, in any event, US public support for the
‘War on Terror’ remains high and largely unquestioning. In the less devel-
oped countries, nationalism without democracy is quite common, but the
state rarely has the capacity both to control its own armed forces and to
ignore the disaffection of its people. Riots and civil unrest can be every bit as
effective in influencing war aims as a democratic media and free elections.
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