Teribus says:

"So let's agree on the first of the points raised by Keith A when he said that historians who have studied the period armed with the latest information on the events and background of the period say that

1: The First World War was not a war of choice for the United Kingdom it was a war of necessity.

The British Cabinet and Parliament felt so at the time and it was they who were faced with the problem. They made the right decision, they had no other choice."

Certainly not all historians, and maybe not even most historians, and we certainly do have examples above of historians who don't say this. But seeing as historians were not the ones fighting and dying in the trenches, their perspective is a bit limited. I would take Harry Patch's opinion when he said:

"When the war ended, I don't know if I was more relieved that we'd won or that I didn't have to go back. Passchendaele was a disastrous battle – thousands and thousands of young lives were lost. It makes me angry. Earlier this year, I went back to Ypres to shake the hand of Charles Kuentz, Germany's only surviving veteran from the war. It was emotional. He is 107. We've had 87 years to think what war is. To me, it's a licence to go out and murder. Why should the British government call me up and take me out to a battlefield to shoot a man I never knew, whose language I couldn't speak? All those lives lost for a war finished over a table. Now what is the sense in that?:"

[Cut and paste from Wikipedia before anyone points that out]

Over the entire cohort of historians who have written on this subject.