By the middle of the 1930s it would take an effort of intellectual will to believe that either untrammelled capitalism or communism held much future for humanity. None the less, some tried: George Bernard Shaw visited Ukraine in those years and reported that there was no such thing as famine; indeed, he claimed to have enjoyed one of the best dinners he'd ever eaten.
And in between - both geographically and ideologically - these twin theatres of desolation and devastation, large areas of Western Europe were falling ever further into the deadly grip of fascism. As Philipp Blom concludes in his account of the interwar era, these were "not so much years of peace as a continuation of war by other means".
This is an enthralling masterpiece, epic in scale and human in detail. Blom makes no attempt to be comprehensive and eschews political and economic machinations, focusing instead on a handful of key social and cultural moments that define his central themes: the crisis of values in the wake of World War I, and the seemingly inevitable descent into yet more slaughter.
Some of Blom's subjects are less than obvious - the building of the Soviet steel city Magnitogorsk, the burning of the Palace of Justice in Vienna - while others seem inevitable: Prohibition in America, and the uncluttered modernism of the Bauhaus designers.
Whether familiar or not, all are illuminating and add to the impressionistic, panoramic picture of chaos and unrest. Just as importantly, all are compelling, for Blom is a masterly storyteller, with a taste for atmosphere and drama, continually finding new angles, details and juxtapositions. One moment we're being shocked by the raw sensuality of the American dancer Josephine Baker in Paris, the next we're plunged into the uncertainty of the subatomic world being uncovered by theoretical physicists.
Along the way we discover that, after the Bible, the second-most popular book among German soldiers in the trenches of Flanders was Nietzsche's philosophical novel Also Sprach Zarathustra, and that the 1920s dance craze, the Lindy Hop, was named after aviator Charles Lindbergh.
We also encounter famous people in unexpected circumstances. Here's Hollywood producer Sam Goldwyn flying to Vienna to offer Sigmund Freud $100,000 to write a love story for a movie (and being turned down).
Here's the century's most notorious mobster, Al Capone, sufficiently concerned about the effects of the Wall St Crash that he's opening a soup kitchen on the Chicago streets.
And, most magnificently of all, here is the Conservative MP, Nancy Astor, in Moscow in a private audience with Stalin, protesting about his murderous policies and concluding: "I think you are all awful!" That, surely, is speaking truth to power.
The tone is inevitably dark and it becomes more so as the frenzied euphoria of the Flappers and Bright Young Things of the 20s is eclipsed by the muscular utopianism and barbarism peddled by communists and fascists alike.
But there are rays of hope to be found, most notably in the rise of popular culture.
"No dictatorship has ever approved of jazz," writes Blom, and the liberating impact of the jazz revolution is given serious weight.
So, too, is the black artistic explosion that became known as the Harlem Renaissance, complete with the disdainful wit of writer Zora Neale Hurston. "It merely astonishes me," she said, when asked about segregation in America. "How can anyone deny themselves the pleasure of my company?"
In all this, Britain is, for the most part, confined to a supporting role, appearing insular and peripheral. Blom, who was born in Germany and resides in Austria, is more interested in the wider picture, and in the context of Hitler, Franco and Mussolini, he's probably right to dismiss the importance of Oswald Mosley.
The massive upheavals of World War I destroyed all sense of certainty and continuity in the West. The political earthquake - four empires fell, the map of Europe was redrawn - was matched by intellectual and moral confusion. Blom depicts a world suffering from a collective shell shock, with politicians and preachers, artists and scientists struggling to make sense of what has happened, while the masses cling on in desperation.
It may not have been the end of the world, but reading this tremendous book it feels as though it were at times a close run thing.
Fracture
by Philipp Blom
(Atlantic $32.99)
- Canvas, Telegraph