By John Gittings
A significant achievement of this book – and one which is central to its purpose — is its re-discovery of the pursuit of peace as a constant theme of the internationalist argument which began after the Napoleonic wars and has continued in one form or another till today. Mazower provides almost a counter-narrative to the conventional history of modern Europe which has so often marginalised peace thinkers and peace organisations or ignored them altogether. (A J P Taylor did not even mention the Hague Peace Conference of 1899 in his The Struggle for Mastery in Europe 1848-1918).
The abiding cause of the new internationalists after 1815, Mazower writes, was “the battle for peace”  and an extraordinary network of small local peace societies soon sprang up across the US and Britain. Originating with dissenting and evangelical thought, by the 1840s the movement had spread into middle-class circles and become more respectable. It was endorsed, for his own purposes, by Louis Napoleon in France and the peace congress held in Paris in 1849 – speakers included Victor Hugo and Richard Cobden – had his approval. Soon after the peace movement suffered its first of many setbacks: it was divided as to whether or not to support revolutionary action, it was wary of criticising established regimes, and it was almost silenced by the war fever stirred up by the Crimean War. But, as would become a characteristic of peace advocacy, it learnt from this setback: there emerged “a more chastened internationalism”  which relied less on appeal to Christian principle and more on building new international institutions which, it was hoped, would provide “indirect paths to peace.
The first of these was the founding of what would become the International Red Cross in Geneva and its first Convention in 1864. The horrors of war, witnessed in 1859 by Henri Dunant on the battlefield of Solferino, led to the first efforts not to stamp out war entirely but to face “the legal challenge of humanizing the way it was conducted” . More generally, it became accepted that new forms of war required new rules to regulate it. By the start of the 20th century, “international law was the pre-eminent example of a once utopian internationalist creed harnessed and tamed by states themselves” .
These developments illustrate another feature of the peace movement: as the reality of war became more visible (thanks largely to modern reporting from Crimea onwards) and more lethal, so the quest for methods of taming war became more vocal and purposeful. However Mazower notes two other less positive consequences. The first was that outright opposition to war tended to become a separate preserve of those who would later be labelled as “pacifist” (though this word did not acquire its absolutist meaning until the 1920s and ‘30s). Second and perhaps more serious was that the approach designed to codify the rules of law between “civilised” sovereign states—and those who signed up to the 1899 Hague Convention — by the same token “did not apply to ‘savage peoples’ since they lacked a recognised sovereign” and were not signatories . Mazower puts the consequences of this very strongly: Legal theory, he argues, would be translated into the “massacres, aerial bombings and systematic detentions” that would characterise European imperialism for decades to come. The new internationalism thus adopted two different forms, one which endorsed peace at least in words in Europe, and another which legitimised aggression outside Europe.”  The difference persisted at least until the Second World War when European nations fighting in the name of civilisation had no scruples about treating one another with the same ferocity and the same “methods they had once reserved for ‘savages’”  There is a sense (as Mazower points out) in which this still applies today. The rules of war need not apply to those who wage it unconventionally or asymmetrically and can be lumped under the “terrorist” heading.
The 1899 Hague Peace Conference did produce some notable results – notably its outlawing of the use of chemical weapons which has survived with huge contemporary relevance. One cannot however disagree with Mazower’s conclusion that the powers attending the conference did so chiefly “for fear of criticism if they did not” , though one might add that this at least demonstrated that peace advocacy had made a great (though not sufficient) advance in the late 19th century. The second conference in 1907, while generally even more disappointing, did achieve one practical result by establishing a new machinery for interstate arbitration – the Permanent Court of Arbitration at the Hague which continues in existence, though with limited effectiveness, today.
This legalist route to peace – the belief that in time war could be prevented by the decisions of what would hopefully emerge as a supra-national world community – did not survive the First World War. Yet the war did compel the great powers to accept that peace could not be preserved by a concert of nations and that some sort of internationalist structure – however limited its authority – was needed. Mazower shows how Woodrow Wilson played a critical role in the formation of the League, yet the British without whom it would not have got off the ground were also persuaded – though it was “a hard sell” . The League, he concludes, was “ an extraordinary diplomatic innovation, a realization of the dreams of many nineteenth-century internationalists and a moment of truth for others…. It reached back to the radical impulses that had emerged a century earlier in the reaction to the Concert of Europe.” 
The League, as everyone knows, would turn out to be a “failure” – failing to prevent, or find remedies for, the string of aggressive actions, from Manchuria to the Anschluss, which led the world into its second war. Mazower points rightly to the League’s obvious weaknesses: an unwieldy quasi-parliamentary structure, the very openness of its diplomacy which encouraged posturing and grand-standing, the lack of means of enforcement and particularly the lack of a standing force. Disarmament, the first of the two great objectives of Versailles, remained an empty vision, though Mazower has perhaps under-estimated the chance that the 1932 Disarmament Conference might have achieved something, especially if it had been held just a couple of years earlier before the rise of Hitler (some of its participants — including the young Anthony Eden! — thought so). Less conspicuous but more lasting was the League’s successes in forming an effective secretariat and promoting international organisations for health, labour and economic reconstruction. By the late 1930s, more than half of the League’s budget went into these “technical” services . This strand of inter-war internationalism was not interrupted by the second world war but laid the basis for similar work by the UN. The strengths and weaknesses of the League as a whole carried through to the new post-war international organisation, seeking “to marry the democratic idea of a society of nations with the reality of Great Power hegemony” . Often for worse but often also for better, that is where we have been since 1945 and still are there today. As Mazower shows us, we are the inheritors of a peace narrative which can be traced back over the past two centuries – and indeed more.