Did the promise to defend Poland cost Britain its empire?
Was Britain to blame for World War II? Did decisions made by Winston Churchill after 1940 lead to the Holocaust?
One right-wing commentator and former presidential candidate from the United States contests the conventional view that the Nazis were solely responsible for starting WWII.
Patrick Buchanan's theory is that the war which ravaged Europe from 1939 to 1945 was not the inevitable consequence of Nazi expansion.
Instead, he says, it was the decision to give a guarantee of defence to Poland, despite having no intention or ability to protect it, that forced a war upon western Europe which Hitler did not want.
Buchanan claims that without this guarantee the Nazis would have been content to expand into eastern Europe and would, by and large, have left the western European democracies alone.
"The colossal blunder of the British Empire was ever in extending a war guarantee to Poland. It did not save Poland and it cost Britain its empire," he says.
'No war, no Holocaust'
Would the Holocaust have happened if there had been no world war?
Buchanan goes further and states that had Britain not forced war on Germany, the Holocaust would never have happened.
He suggests that the "final solution" was only enacted in 1942 once the war was all but lost.
"The annihilation of the Jews was the price the Nazis imposed for their own annihilation.
"If there had been no war, I do not believe there would have been a Holocaust.
"The price of stopping Hitler was this: 50 million human beings dead, the Holocaust, Joseph Stalin taking over 10 Christian countries, the communisation of China.
"I think that is a failed policy," he says.
So how do Buchanan's views fit with those of academic historians?
If there had been no war I do not believe there would have been a Holocaust
Richard Evans, a professor of modern history at the University of Cambridge, completely disagrees with Buchanan's hypothesis.
"It is a fundamental misconception.
"There is widespread agreement that Hitler intended to subdue western Europe, create an enormous German empire and then confront the United States."
"Buchanan fails to recognise the limitless ambition of Hitler," he says.
Evans also denies that the Nazis only contemplated the holocaust when they were loosing the war.
"Hitler began to exterminate the Jews in the Autumn of 1941.
"At that time the Nazis were utterly convinced that they would be victorious in the war," he says.
Trying to re-write history
Hitler's motives are still disputed
But Richard Overy, professor of history at Exeter University, thinks that Buchanan's theory is "not an entirely implausible position".
Overy says that questioning the causes of the war is "still regarded 70 years on as something quite unacceptable".
He says that it is good for people like Buchanan to articulate ideas that historians are afraid of saying.
"But the problem is that war did break out.
"As historians, we can't re-write history. One might argue that there were other outcomes possible, but once you twist the dial a different way, you create a number of outcomes which you simply cannot know."
Was Hitler an evil force who had to be stopped or could World War II have been avoided?
Mr Buchanan struck me as an intellectual fool. Hitler and the Nazi regime were about their evil work well before the outbreak of WW2 and Churchill was one of the few who was taking any notice. The notion that Great Britain should have stood by for Empire's preservation alone and that should outweigh any support of a threatened friendly nation is contemptible. Warren Kerfoot, Hyde, Cheshire
This is a provocative perspective, but I wonder whether life within the Soviet sphere would have been more or less terrible than it would have been under the Nazis - who, after all considered Slavs to be subhuman and suitable only for slave labour. Buchanan's views are in support of expedience over morality but the intentions of the West were honourable, even if the results, in the end, were bitter-sweet. The question really boils down to whether an idea is worth dying for or if it's better to keep your head down and profit from the situation if you can like, say, the Swiss. N Baxter, Cambridge , UK
WWII in this country is a bit like the NHS. It cannot be questioned in any way for fear of being branded a heretic. We have simply invested too much in either for any rational debate. No wonder Clarkson can still get a laugh talking about German invasions in the car industry, when the rest of Europe scratches it's head in puzzlement as to why we are still banging on about it, a lifetime later. Why is Pat Buchanan 'evil' for voicing an interesting historical 'what if' when Tony Benn, who is an apologist for Stalin's USSR, is a national treasure! Bernardo, London
Given the record of Pat Buchanan and his ilk in supporting Fascist regimes in his own hemisphere we should not find this man's odious crackpot views surprising. Ian Young, London
Mr Buchanan blames the Holocaust on the fact of war, and the war on the British. Thus we, and in particular Winston Churchill, were indirectly responsible for the murder of millions of Jews, gypsies, communists and other people deemed by the Nazis unworthy to live in the thousand-year Reich. Such a view flies in the face of reason and history. I'd remind listeners of another outspoken American, Joseph Kennedy, the U.S. ambassador here when the war started. He made plain his view that Britain was finished, that the British government should seek peace with Hitler whilst it had the chance, and that the U.S. shouldn't waste its time supporting Britain. President Roosevelt recalled him. Thank goodness Patrick Buchanan wasn't in charge of British or American policy in 1939 and the following years of war! Mike, Cardiff, Wales
How can Hitler's motives ever be disputed? They are there for all to see, for Patrick Buchanan to doubt them that says a great deal of his politics, he is being either; na´ve; gullible; or disingenuous, from listening to his arguments he appears to be the latter in short an apologist for if not exactly a closet Nazi. The holocaust would not have happened if Churchill had accepted Hitler's offer of rapprochement and the Nazi's only resorted to it as act of expediency, is obvious nonsense as Hitler was assiduously laying the foundations of his 1,000 years Reich before WWII. Barry Cross, Hatfield, England
Patrick Buchanan should read Robert Jay Lifton's classic work "The Nazi Doctors" which shows how the idea of "life unworthy of life" infiltrated the Nazi regime well before 1939 and inevitably lead to the Holocaust and other atrocities. Chris Knight, Oakham, Rutland, UK
Revisionist history is a dangerous thing - Hitler's intention for the Jews was perfectly clear in Mein Kampf - and Crystallnacht was well before disasters on the Eastern front. Most war is insupportable - like the one Israel would love to involve us in over Iran, but Hitler and co were very bad guys indeed and had to be stopped - thank heaven we moved on from appeasement in time! Warren Feagins, Maidenhead Berks
Interesting thesis. If he is right then the vilification that has traditionally been extended to the architects of 'appeasement' in Britain should be re-evaluated. It does however seem to depend on cherry-picking from Hitler's ambitions, focussing on the more limited ones, and perhaps also does not account for the fact that Hitler was not a 'rational actor' but a psychically damaged individual who might have changed his plans once he had achieved success in Eastern Europe. Guan, Norwich UK
We all know that Hitler was an evil man. I should be apparent that Pat Buchanan is also an evil man. Please next time you have a nasty bigot like this on the show have someone else to argue the counter point. Dave Webster, Perranporth Cornwall
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