This website suggests that the central driver towards war in the last hundred and fifty years has been the manufacture, marketing and use of arms. The point is encapsulated in the warning of Jesus: Those who take the sword perish by the sword."
The central answer which emerges to the question: Why World War One? is: Arms cause Wars. This was the conclusion of Sir Edward Grey and other statesmen of the era and we have only forgotten the conclusion because we have become immersed in a weapon-normal culture. Yet the process is decisive and happens through a variety of processes which we try to set out here.
1.FAITH IN WEAPONS. Arms are made for fighting and war. they are not neutral, but purposive. Weapons are meant to fight wars. When states and other groups buy arms, they express the value they give to their possession and they come to trust in them. Sooner or later they will be used as an answer to a set of problems. In WW1 Russia, Germany, Britain, France, Austro-Hungary and the Ottoman Empire had all developed a faith in weapons for different reasons.
2. ARMS KILL AND DESENSITIZE STATES TO MASS MURDER. If you buy weapons, you have come to terms with their possible use, which involves killing people and destroying areas. Gas and dum dum bullets, might seem particularly inhumane, but the deaths and injuries of war are all inhumane and even horrific, yet the business of war means that we harden ourselves to the process. The Ottoman Empire's massacres of the Armenians, Austro-Hungarian atrocities in Serbia, German acts in Belgium and dozens of other atrocities in the Great War happened because of the possession of weapons.
3. WEAPONS CREATE FEAR AND DISTRUST. When states buy weapons, other states tend to become fearful of attack and themselves arm. By now we should have worked out that buying arms leads to the other sides being armed. Arming leads to arms races. everyone escalates their arms purchases and the size of their military. This happened over five decades leading up to 1914. However, the heavily armed countries are also themselves afraid. Germany was deeply fearful of being attacked on two sides. Britain was paranoid about naval supremacy. This may be because trusting in weapons is distrust of other states.
4. WEAPONS CREATE MILITARY DICTATORS. The build up of weapons and soldiers predisposes states to a government where the military are at the centre of power. Western weapons have created military dictatorships or militarised states throughout much of the world. In the two decades before 1914 Britain and Germany militarised the Ottoman Empire and a series of coups followed. Britain's provision of a Navy did the same in Japan. France and Britain armed Russia and helped the military to be in charge. We have had hundreds of military dictators this last century put in place by purchased weapons.
5. WEAPONS CREATE DOMESTIC ECONOMIC WEAKNESS. Churchill made this point in relation to Germany. If a state spends a lot on armaments and the military, it is money removed from normal productive economic activity. Normally it has to be addressed by taxation and debt. the effect is to create economic weakness which may drive economies towards war as a distraction from the emerging economic crisis. This pattern was probably present in Russia, Germany and Austro-Hungary.
6. SOONER OR LATER THE MILITARY MUST FIGHT TO VALIDATE THEIR POSITION. Especially when the military are strong and well-armed, sooner or later they must fight to show that they have some purpose. They also face their own internal crises which require war as an answer. It is also the case that the more bellicose elements in the military tend to seek promotion and power.
7. WEAPONS FALL INTO THE WRONG HANDS. Weapons travel and are passed on. Often they leach from official armories. Frequently, weapons are sold on by reputable or unreputable dealers. An illegal order just means a higher price. Once the weapons are made, they gravitate to the people who will misuse them.
8. THE ARMS COMPANIES AND THE MILITARY TALK UP THEIR WARES. Arms companies overclaim for their weapons. Many arms fail, or are countered, or do not fit the conditions. Germans used gas on the western front against the prevailing wind. Often the military cannot perform as they claim. The outcome is that optimistic claims are made for wars which in the outcome are lost, long or indecisive. Wars are entered
9. WEAK LEADERS GO FOR EXTERNAL WARS. Frequently when political leaders face internal divisions or political weakness, they look for an external scapegoat. Blaming outsiders is a way of deflecting criticism and a war against a suitable adversary seems a way out. Both Tsar Nicholas and Kaiser Wilhelm seem to have made this move, and it led in the end to the demise of both. It has happened frequently since.
10. THE ARMS COMPANIES AND MILITARY TALK AS THOUGH WARS WORK, BUT WARS DON'T WORK. They didn't work for Austro-Hungary, Russia or Germany, the original trio in World War One. They often do not work for the "victors", because of devastation, death, economic ruin. They don't work now in Iraq, Afghanistan or Syria. The military and weapons people won't admit that wars don't work. They sell a bum rap.
All of these processes add up to the fairly universal process whereby those who arm finish up going to war. "Those who take the sword, perish by the sword." If the move doesn't work, let's try something else.