The ‘methods’ the German officer corps permitted to be used against civilian populations, especially on the Eastern Front, were far worse than Jodl’s weasel words implied. Those officers were almost universally deeply implicated in monstrous abuses of every canon of the rules of war, written and unwritten. Jodl’s explanation that the partisans ‘used every – yes, every – single means of violence’, and that the Allies ensured that ‘hundreds of thousands of women and children were annihilated by layers of bombs’ cannot excuse the Axis methods of warfare.

If Jodl had known the true story of why Allied intelligence so regularly outwitted the OKW – owing to the Ultra information gained from decrypting the Enigma codes – he would undoubtedly have added another line of defence for the High Command. Ultimately, however, Jodl’s excuses are not convincing: the German generals did indeed serve ‘a criminal’, as well as the Volk and Fatherland.

The German people nicknamed Nazi Party functionaries ‘golden pheasants’, but none were more heavily gilded than the Wehrmacht generals. ‘Nor could they plead ignorance about what was involved,’ points out historian David Cesarani in relation to their refusal to apply the Geneva Convention on the Eastern Front and elsewhere. Hitler ‘regularly briefed his party followers, ministers and military men about his racial goals. Occasionally some demurred… but most cooperated. By 1939, thanks to Hitler’s successes, his popularity and his style of rule, there were no alternative centres of power capable of stopping him or willing to try.’

The SS and other state institutions in particular were deliberately kept separate from the Wehrmacht. This could have been operationally frustrating for the generals. It was also true that Admiral Wilhelm Canaris, head of the Abwehr, thought Hitler a ‘madman’ and had been in communication with the Allies towards the end of the war, although his organization did not systematically aid the enemy, as Jodl alleged.

Their fathers and grandfathers had shot French francs-tireurs in the Franco-Prussian War and had ill-treated Belgian and French civilians in the Great War, so the supposedly noble Prussian military tradition was always something of a myth. The oath they swore to Hitler personally could not excuse them.

Their motives included natural ambition, criminal complicity, genuine patriotism, lack of an alternative, professional pride, an understandable desire to protect their loved ones from Bolshevik vengeance, a desperate hope for unexpected victory, Nazi faith in many cases, but probably above all simple loyalty to their men and brother officers.

Just as no one was shot for refusing to execute a Jew, so German generals put only their jobs, rather than their lives, on the line when they crossed Hitler on a point of military principle. Very often they were brought back from enforced retirement to serve again, as happened to Rundstedt three times. They might therefore have been ‘only obeying orders’, but they were not doing so out of a well-founded fear for their lives.

Albert Speer wrote to Otto Thierack, the Nazi Minister for Justice, saying that he wanted to testify as a character witness for General Friedrich Fromm, who had ‘maintained a passive stance’ towards the Bomb Plot and not warned the authorities about it. If anyone had done such a thing in Soviet Russia, it would have been considered a suicide wish. It did no good: Fromm was executed by firing squad.

Admittedly, some of the Nazis, such as Julius Streicher, who pronounced that Jesus Christ was ‘born of a mother who was a Jewish whore’, conformed precisely to type. Mainly, however, they argued vehemently that they had known nothing about the Holocaust, and claimed they would have resigned if they had known that Hitler planned war, but could not do so after it had broken out, for moral and patriotic reasons.

Yet for all their lies and claims to have constantly stood up to Hitler – Kleist even claimed to have regularly shouted him down at meetings – the fact remains that virtually no one voluntarily resigned from a position of power, even when the war was clearly going to be lost.

General von Kleist told historian B.H Liddell Hart after the war, ‘Under the Nazis we tended to reverse Clausewitz’s dictum, and to regard peace as a continuation of war.’ It is not difficult to construct a narrative of the Second World War in which a Chiefs of Staff committee of German generals did not make the blunders Hitler did.

Hitler’s defeat was intimately tied up in the political nature of Hitlerism, in particular his refusal to retreat, his belief in the power of his unfettered will and his constant upping of the stakes, which had worked well for him in Weimar domestic politics in the 1920s and in his international brinksmanship in the 1930s.

Hitler could not have left soldiering to the soldiers. A Führer had to be a superman, equal to any calling, and for such a spectacular know-it-all as Hitler – with views on everything, a love of military history and an impressive recall of military facts – the prospect of taking a back seat in a world war was an emotional and psychological impossibility.

Nazi philosophy contained within it, once translated onto the military plane, the seeds of its own destruction. An expansionist nationalist German without a Nazi worldview – another Bismarck, say, or a Moltke – would probably not have defeated the USSR either, but he would have made the war go on even longer and claim even more lives.

Historian Alan Clark pointed out, ‘There is no evidence that Hitler ever changed his mind on questions of strategy either at the persuasion of his intimates in the Party or the senior officers of the Army.’ If Hitler and certain generals agreed on something, it was almost always because they agreed with him rather than vice versa.

It was said of Emperor Napoleon III that his name was both his making and his undoing. Similarly, Hitler won his revolution because of his drive, willpower, impulsiveness, philosophy and policies, which seemed – however wrongly – to offer Germany hope in the 1930s. Yet it was precisely these same phenomena that led to his destruction the following decade.

The generals cannot be seen as a unified voice: Zhukov, Konev and Rokossovsky were rivals, just as Patton, Montgomery and Bradley were on the other side of the conflict. The dismissal of one German general was usually seen by the rest as an opportunity.

German Jews who had fought bravely for the Kaiser were not only not called up for the Volkssturm, they were gassed. Between 1939 and 1944 the German labor force shrank from thirty-nine million to twenty-nine million people, a disastrous 26 percent fall at a time when a massive increase in production was vital for victory.

While production was being badly hampered by the lack of intelligent, educated, hard-working people, Hitler massacred some six million Europeans Jews, an action that would be evidently self-defeating, except to the diseased mind of a Nazi fanatic.

For all the military defeats on the European Continent to both the east and west by 1945, there was one thing that could still have won Hitler a stalemate, or even the war. In 1942, the German physicist Werner Heisenberg reported to Hitler that an amount of uranium ‘no larger than a pineapple’ would be enough to destroy a city. Yet the Jewish and German émigré scientists who had the knowledge and genius necessary to split the atom were by then working in New Mexico, rather than for Heisenberg in the Kaiser Wilhelm Institute in Dahlem.

In the two areas where pure intellect had an appreciable influence on the outcome of the war - the cracking of codes at Bletchley Park and in the Far East, and the creation of a nuclear bomb at Los Alamos - the Allies won the battle of the brains.

Up until the end of 1944, on a man for-man basis, the Germans inflicted between 20 and 50 per cent higher casualties on the British and Americans than they suffered, and far higher than that on the Russians, under almost all military conditions. Although they lost because of their Führer’s domination of grand strategy as well as the sheer size of the populations and economies ranged against them, it is indisputable that the Germans were the best fighting men of the Second World War for all but the last few months of the struggle, when they suffered a massive dearth of equipment, petrol, reinforcements and air cover.

Only after the German reverses at Stalingrad and Kursk could the Russians start to impose their will upon the battlefield, which they eventually did with great vigor, especially in 1944. The destruction of Army Group Center during the Bagration offensive in the summer of that year was as decisive as anything seen in the history of warfare. It utterly dwarfed the contemporaneous Operation Overlord. Advances on the Eastern Front were still costly, however, for even in 1945 the Germans were inflicting more losses on their opponents than they suffered themselves. This was not the case in the west, however.

Theoretically the Americans could have pursued a Pacific First policy. But General George C. Marshall rightly considered that while it would be relatively easy to defeat Japan after a German surrender, the opposite was not necessarily the case. The strategy whereby American forces first engaged German forces in North Africa, then Sicily, then Italy before finally squaring up to them in north-western France was effectively forced on the Joint Chiefs of Staff by the British, who vetoed any recrossing of the Channel before 1 May 1944.

After the Germans introduced an extra rotor to the Enigma machine, the Allied navies were plunged into the dark over Kriegsmarine movements in the battle of the Atlantic for almost a year. No landings in north-west Europe could be attempted with supply lanes at the mercy of the U-boat fleet. That battle was not won until May 1943, by which time a quarter of a million Germans had surrendered in Tunisia and plans were well under way for the invasion of Sicily.

Marshall might have complained about being led ‘down the garden path’ by Brooke and Churchill, but at the Casablanca Conference of 1943 he had to acknowledge that there was no possibility of crossing the Channel in any significant numbers that year. The war could not be simply suspended until enough men had been assembled in southern England for Overlord. Sicily followed Africa logically, just as Italy followed Sicily.