Hello, and thanks for the question.
The causes of war between nations are as various as the causes of
arguments between married couples. Like couples, nations deal, from
time to time, with interests unique to them. Conflict may become
Walter S. Jones' book, The Logic of International Relations (7th ed.,
1991, Harper-Collins), Chapter 11, "Principal Causes of War," is a
very good run down on the main reasons.
He lists the main causes of war as follows:
1. Power asymmetries
War can happen when one nation sees a chance or a necessity to use
violence to attain its goals when it spots a "weakness" in a perceived
2. Power transitions
Any change in system distribution of military capabilities will bring
new opportunities for war e.g. if one country in an unstable region
gets a large military advantage, either from its own efforts, or by
being given it by a "friendly" state, then tension will automatically
increase, and war is more, rather than less, likely.
3. National integration - separatism (sovereignty), irredentism (join
Countries will go to war to protect sovereign boundaries if they think
they are being "squeezed", or if they think that their leaders are
trying to "merge" them with other countries. Also, there can also be
an upsurge for a "historical" nationality that has been overtaken by
events. This is especially true in countries that have had their
boundaries redesigned by treaties after previous wars, for example, in
the Balkan States.
4. international social darwinism
Belief systems, especially where one country believes it has a right
under "survival of the fittest", believe that warfare can purge
weakness. Probably the best example is Nazi Germany, and its quest
for "racial purity".
5. communications failure - secrecy, misperception of motives
Some countries are "hooked" on secrecy. And some other countries are
paranoid about what the other country is hiding. This can lead to
increased tension, misunderstood motives, and a higher likelihood of
war. A good example is in the Wests dealings with communism, with
paranoia and distrust (on both sides) leading to heightened tensions,
and war coming close on several occasions, as in Cuba 1962.
6. communications failure - technical errors
In these hi-tech days there is a great potential for a war merely due
to a technological failure, for example, if a missile defence system
mis-identified a meteor storm as a missile attack, and couldnt
contact a supposed "aggressor" for confirmation, it could easily
escalate into conflict.
7. arms races
Military preparations are most often based on worst case scenarios,
which means the country develops huge numbers of armaments. This leads
to other countries developing their weapons in parallel, until tension
is racked to breaking point. A current example seems to be playing
itself out in India and Pakistan at the moment.
8. internal cohesion through external threat
Some countries build support in their population by constantly
drumming up hatred against a perceived enemy. This -does- built a
united front, but leads to increased tension in the country, and fear
of attack. It also leads to tension in the country that is being
portrayed as an aggressor. You could say that this is mirrored in
Iraq, ith Saddams hold over his people based in part on a perceived
threat of American attack.
9. international conflict through internal strife
Internal breakdown precipitates external intervention, leading to
proxy wars for instance eg in Vietnam, internal conflict led to
another country, USA, being drwn into war.
10. relative deprivation
Frustration causes aggression , especially in cases where an under
privileged majority does not share prosperity with a ruling minority,
as in Russia in 1917.
11. instinctual aggression
There is a view that wars are human nature - people enjoy using
violence to attain goals. That certainly seems to be the case in some
totalitarian regimes, such as the former East Germany, or in some
South American Dictaorships.
12. economic/scientific stimulation
New technology can bring new weapons, new hopes and lead a country to
start looking at areas where it can expand, and increase its ambitions
eg the British Empire, which began to expand exponentially when
Britian achieved technological superiority after the Industrial
13. profits made in war, support other wars
This is the "money talks" argument. Wars are good for business, with
armaments needing to be made, troops needing to be fed, buildings that
are destroyed needing to be rebuilt etc. There is a belief that some
countries go to war just to provide opportunities for business.
14. population limitation
Some wars occur when a country simply runs out of space and its
population has to go somewhere.
15. conflict resolution
Sometimes, when argument fails, some countries see force as simply
another means of resolving the conflict, eg, the Argentinians invaded
the Falkland Islands out of frustration that it was getting nowhere in
All that is all well and good, but it still doesnt answer the simple
question of why people would kill other people. You would think that
seeing the horror on TV every night would put an end to it, but it
In another view, in a book: On the causes of war by Michael Andregg
he concluded that the ultimate causes of war are embedded in human
nature itself; therefore, the possible triggering mechanisms are many
and varied. More than half of his book is an exploration of 20
specific proximate causes of war and how they work. These include: the
competition for resources and power, population pressure,
authoritarian law and militant religion, corruption of governance,
nationalism, "forces of evil," and spies, cults, and secret power
With regard to each of these proximate causes, Andregg attempts to
calculate its effect on the probability of war by using a predictive
instrument called the "Three Green Lights" model. According to
Andregg, organized, state-sponsored killing requires
(1) decisions by leaders of a government;
(2) support from a population; and
(3) physical means for killing (i.e. weapons).
If these three "green lights" are not reciprocated in the targeted
nation or group, the result is genocide. If they are reciprocated, the
result is war. The presence or degree of contributing proximate causes
affects the likelihood of the three "green lights."
The above is abstracted from a review of Andreggs book at Yes!
Magazine book reviews site:
Winston Churchill, as far back as 1934, said in a BBC Broadcast:
"Many people think that the best way to escape war is to dwell upon
its horrors and to imprint them vividly upon the minds of the younger
generation. They flaunt the grisly photograph before their eyes. They
fill their ears with tales of carnage. They dilate upon the ineptitude
of generals and admirals. They denounce the crime as insensate folly
of human strife. Now, all this teaching ought to be very useful in
preventing us from attacking or invading any other country, if anyone
outside a madhouse wished to do so, but how would it help us if we
were attacked or invaded ourselves "
He also had this to say on how to solve it:
"To remove the causes of war, we must go deeper than armaments. We
must remove grievances and injustice. We must raise human thought to a
higher plane. We must give a new inspiration to the world. Let moral
disarmament come and physical disarmament will soon follow."
Hope that answers your question, but if you want any clarification,
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