Sir Hew noted that beyond the old British Empire, the war had profound implications for defeated Germany, for France, whose losses were double those of Britain, for the Muslim world affected by the collapse of Ottoman rule and even for the United States, which by war's end had the largest army on the Western Front.
In Britain, one survey found that only 35 per cent of the UK population were aware that New Zealand and Australia fought alongside the British Army.
Another UK poll found a big majority in favour of marking the centenary. But only one in five felt that the Commonwealth contribution - from Downunder, the Pacific Islands, Douth Africa and across the Indian subcontinent which raised more than one million men for military service - was sufficiently acknowledged.
Regarded as one of Britain's foremost military thinkers, Sir Hew sits on the Chief of the Defence Staff's Strategic Advisory Panel, and advises the UK Defence Academy, which trains senior officers. He is not afraid to criticise politicians and in a book published this year rebuked London and Washington, saying their lack of clear thinking about strategic objectives meant that wars in Iraq and Afghanistan were bungled.
Sir Hew says there is still plenty to discover from World War I studies. For all who complained that the war was poorly conducted by Allied military generals, Sir Hew suggested they look at recent conflicts, such as Iraq or Syria. They hardly unfolded the way that politicians predicted, which had its echoes in the confident but misplaced line that World War I would be "over by Christmas".
The point being, Sir Hew said, that the causes of war and the way they were waged needed to be judged according to the circumstances of the times.
Sir Hew, the author of numerous accounts of the war, considers that historians still have plenty to argue about over the painful conflict. He believes there are fresh areas to explore, from a perspective of gender studies and economic impacts. If the millions earmarked for commemorations - New Zealand's budget is $20 million; Britain has set aside 60 million ($118 million) - reached the generations who 100 years ago answered the call to arms, the investment could create a better understanding of World War 1, and of war generally.
• Sir Hew is giving public lectures at Te Papa on Monday, Te Manawa Museum in Palmerston North on Wednesday and Auckland Museum next Friday. See aucklandmuseum.com for details.