So first for me you have to take the two world wars together as the second was a continuation of the first, because of the badly implemented peace treaties after the first. They were a half way house that left some of the Empires intact while dismantling the others and caused the rise of Hitler, Stalin, Mussolini and Japanese fascism. The reasons for this were the unfairness of the treaties to these nations in particular by ignoring their needs or in punishing them. So keeping it to asking should Britain have fought the first world war but looking at the outcomes from both world wars not the first singly is how I would make my argument.
Fergusson is right that without Britain entering it would have been a short war with French and Russian defeats in months or a year at most. There would have been a much lower loss of life. It would have been the Franco-Prussian war part II with a Russian excursion. Whether this would have been enough to trigger the Bolshevik revolution you cannot know. Russia would probably have continued its sequence of small revolutions but it might have developed into a constitutional monarchy. Although given the last Tsar's beliefs and the nature of Russian politics at the time I doubt it and so an eventual revolution would have happened, although probably not as soon. This would also have been more likely contained like that in France 150 years before, especially with a bulwark of a strong Imperial Germany. France would have lost some territory and the great game would have been reset with its inherent instability after the end of the congressional system that had regulated affairs between the powers since Napoleon and with the growth of the US.
It is the growing super-power desire of the US and Germany that would have been challenging to deal with. The US had already had colonial excursions fighting the Spanish to free Cuba and the Philippines and they had plans for a conflict with the British Empire. Canada was a particular embarrassment while it remained British. How the US would have dealt with a short French/Russian German/Austrian war we cannot say except there would have been no push for National Self-Determination. There would have been no League of Nations and they could have returned to isolationism or want to open the world to their trade. This trade war would most likely have become a hot war between the US and the old closed trade Empires protecting their interests. Britain would have been the main target for the US and Germany might have used this conflict as an opportunity to push ahead with its own imperial ambitions.
Luckily this never happened and the first world war was the catalytic moment for the end of empires. Although the victorious empires were slow in their retreat the British lost the desire to be the world police force and superpower. They wanted the trappings of being a world power but not the commitments and so the sun was starting to set. It would take the second world war to make this change irresistible but as I said you cannot easily separate the two wars.
What is also important is the social changes the war brought about with the weakening of the aristocratic elites and growth of the power of the working classes and of women. The wars were a huge push for social equalisation and expansion of the franchise. Again this was not an instant change and there were fits and starts along the way but the wars ended the social status quo that had existed since the end of the Middle Ages.
Finally the war created global government. Firstly through the weak League of Nations then through the still impotent UN but more importantly though the EU, world bank, what is now the WTO and the other bodies of international cooperation. Empires were closed and protectionist exploitative and dictatorial. Too many people in the world had no voice, no position and no hope. The wars created international law, they humiliated the Empires, they showed eugenics and racism to be fundamentally wrong and they shaped the modern socialist democracies.
So in conclusion with foresight and for the good of the status quo if you are a neo-liberal Imperialist (like Ferguson) it was a war Britain should not have entered. So I do not agree with Hastings that it was a war that Britain had to enter because it was a war of good, truth and justice against evil. It was not a war to save Europe or the world from a dark age of German/Austro-Hungarian domination. From the British Imperial perspective of that time there was not a lot of difference between the evils of both sides.
But with hindsight it was a war that changed the world immeasurably for the better. The two world wars have been the catalyst to huge social change, world government, the end of aristocracy and of huge movements toward equality in education as well as resources. There is still a long way to go and there are always steps back as well as progress but without these wars the social unrest and internal wars would have cost many more lives and we certainly would not be living in the world that we live in. So we have to thank the millions who died in both world wars for their sacrifice to create this world, but we must not let the current political generation exploit their memory for their own jingoistic and nationalistic views. We must not retreat from the equalisation and world government that the wars brought. So we have to reform and strengthen the UN. We have to make the EU more representative and respected and we have to stop the growth of isolationist nationalism we thought that we had vanquished with the wars.
I was inspired to write this my three books:
- Mark Manzower - Governing the World
- Goran Therborn - The Killing Fields of Inequality
- Ian Goldin - Divided Nations