As with every attempt to predict the future throughout history, some observers were correct and others were almost correct and most were wrong. French General Ferdinand Foch most famously said of the Treaty of Versailles, "This is not a peace, this is an armistice for 20 years." Foch turned out to be one of the most correct, but I think most members of the belligerent nations were fairly happy to believe that there would never be a war as terrible, brutal, and intense as the First World War. Unfortunately, we know today they were very wrong.

I can speak primarily to a Western European perspective, mostly based in Canadian and British views of the war due to my specialization. The idea of a "war against war" was popular throughout the conflict. In October of 1914, famed British author H.G. Wells published a book titled The War That Will End War. It was based on a series of articles Wells wrote where he argued that a victory over German militarism would effectively end war in the modern age. Note that he did not argue that the British were fighting against the idea of war per se - just that if the Germans were defeated war would end. The phrase, "the war to end war," was co-opted among many seeking to fashion some sort of meaning to the bloodshed. It pops up in different contexts among supporters and opponents of the war, sometimes honestly, sometime ironically. In the Canadian context, the war becomes almost a "moral crusade" against German militarism and the German people. When the end of the war arrives in 1918 and the Treaty of Versailles is signed in 1919, most eagerly believed that they their crusade had been justified. After all the death and destruction, surely the victors had forged a better world.

There's many ways you can choose to examine what people believed about another World War, or even just another pan-European conflict. You could search through newspapers for the comments of journalists and politicians. You could examine literature. You could probably trace the public's confidence in avoiding war through the 1920s and its growing doubt in the 1930s as fascism guided European diplomacy back towards conflict. Certainly there are less people believing there would never be another war in 1933, or 36, or 38.

I'd like to present another way of examining the expectation of another war though. The most enduring legacy of the First World War is without a doubt the depositories of stone and metal scattered throughout Europe. We have etched in these memorials and graveyards the names of those who did not survive the fruitless battles of the First World War. For Canada, those markers remind us when the New World came to save the Old one. From low ranking private to decorated Generals, many of the men (and women) who died far from home still lay close to the battlefields that took their lives. For the British Commonwealth, Commonwealth War Graves are filled with thousands and thousands of graves, and memorials like the Menin Gate in Ypres are marked with the names of those who have no known grave. Many of those gravestones hold the final words of their families to the fallen:

Our dead are never dead to us until we have forgotten them

Private John Cameron Roberston, 14th BCI, 3.6.16 (age 29)

He allured to a better world and led the way

Company Sergeant Major Arthur Hamilton Dunlop, 4th CMR, 27.10.17 (age 30)

Sleep, dear son. Honour, Justice, Duty, all survive by your mortal fall

Lieutenant Mackay Mackay, PPCLI, 27.8.18 (age 28)

The Blood of Heroes is the Seed of Freedom

Private Ivor Powell, 87th BCI, 4.9.18 (age 39)

He gave his life to end all wars between nations

Private Malcolm McLean, 50th BCI, 2.19.17 (age 24)

Make firm, O God, the peace our dead have won

Private James Adams Sullivan, CAMC, 8.12.17 (age 19)

Justice owes them this, that what they died for be not overthrown

Private George Franklin Hargrave, 29th BCI, 15.1.19 (age 22)

Memorials erected back home also took on a moral significance. They were built not only as a means of commemoration but as a valuable way of reminding future generations of their ancestors sacrifice. In Canada and Britain, this is captured in the final lines of John McCrae's famous poem In Flanders Field:

Take up our quarrel with the foe:
To you from failing hands we throw
The torch; be yours to hold it high
If ye break faith with us who die
We shall not sleep, though Poppies grow
In Flanders fields

"Breaking the faith" was not just lyrical rhetoric - many believed that it spoke to an obligation to avoid another war. (Some also believe it means to keep fighting the enemy, that is, keep fighting another war.) Canada's most famous scholar on the its First World War memory, Jonathan Vance, quotes Canadian General Arthur Currie: the dedication of memorials was a "trumpet call to service for our fellow men and for our country. It is as if the voices of the dead called to us across the Great Divide bidding us to take courage and to toil for the ideal for which they fell." Or, a Hamilton priest who noted his Church memorial stood "just a few feed from a busy thoroughfare, teaching a lesson of self-sacrifice to a selfish world." Or a shaming Vancouver memorial with the words, "Is it nothing to you, all ye that pass by?" The gravity of the war's consequence on human life was not easily forgotten by those who had lost someone or seen its horrors. Keeping the faith was a strong narrative of Canada's post-war memory, as well as among the other belligerent nations.

There are thousands of examples of memorials and gravestones that speak to the "hope of a better world." I think, to answer your question, there's a clear worry that another war like this could occur. The atrocious nature of modern, industrial warfare was fully displayed from 1914 to 1918, and many feared its return. So how much did its survivors "expect" another world war versus "feared" one is maybe a worthwhile distinction. In looking at these commemorative messages to future generations, its clear that though many may have expected another world war to occur, they fervently hoped its terrible cost could be avoided. After all, many came to the hard truth of the matter: they died for the hope of a better world, not an actual better world. That hope survives through the 20s, and 30s, and you see it again in the memorials of the Second World War. And today, as we perhaps stand on the brink of another terrible conflict, that hope lingers. As it should. After all, our ancestors did not decide to carve these messages into immutable structures of metal and stone so that they could be forgotten.