The death of Henry Kissinger on 29 November marks the end of an era in international politics. The world in which the periods before and after the Second World War were major themes in the considerations of policymakers has gone. Kissinger, through the sheer longevity of his life, constituted a final link to the statesmen of the 19^th century. He possessed not only an assiduous expertise in that century’s nuances but acted as its emissary for the vicissitudes of the Cold War and the United States’ contemporary difficulties. His death at the age of 100 means the fading away of a connection to the era in which the world was upended by conflict and the ultimate ascendancy of US power. Henry Kissinger was a man of three centuries, the last of a kind.

Among his supporters, Kissinger was revered not just for what he did, but for the epoch he represented, in which American power could be cohered into a grand strategy, where different spheres and crises could be constituents of a bigger picture. He was a scholar versed in the politics and ideas of the 19^th century, yearning to resuscitate them for the 20^th and 21^st.

When Kissinger wrote and spoke of figures like Klemens von Metternich or Otto von Bismarck, they were almost as companions rather than subjects. Their period taught that history was a constant cycle between the forces of disorder and the responsibilities of the statesman. ‘The public life of every political figure’, Kissinger wrote in his memoirs, ‘is a continual struggle to rescue an element of choice from the pressure of circumstance.’ In the centuries that he studied and reacted to, the dilemmas and duties were always the same. Considering the grand forces of history and contemporary politics, Kissinger argued in his 2014 book World Order, ‘reconstruction of the international system is the ultimate challenge of statesmanship in our time’. That was his scholarly fixation and his political goal.

The fear of the alternative haunted him. History had the answers but it was also the enemy. In the economic and political disruption of the 1960s and 1970s, Kissinger, as national security advisor and secretary of state, saw US power decaying and feared that it ‘had passed its high point like so many other civilisations’. He warned that ‘History is a tale of efforts that failed’ and ‘I genuinely think that the next decade could either be a period that in retrospect will look like one of the great periods of human creativity, or it could be the beginning of extraordinary disarray.’

Kissinger’s reverence for the great European statesmen of the 19^th century is well documented. What is too often missed, however, is the warning that era offered to him. The Concert of Europe system, so deftly constructed by Metternich and Castlereagh after the Napoleonic Wars, became stale and Otto von Bismarck, with a cold realism and ambitious drive to break the old order – ‘Darwinism sanctified by God’ – upended the balance of power to achieve German supremacy. Yet despite Bismarck’s genius, he precipitated the decline into decades of total war in Europe. ‘Germany, the heir of the Bismarckian tradition of authoritarianism, the Prussian concept of service to the State as an end’, Kissinger wrote, culminated in ‘the Nazi ideology of man’s ultimate realisation in the mass and the establishment of success as the only criterion of values’.

In connecting Bismarck to the rise of the Nazis, Kissinger’s interpretation of the history of Europe in the 19^th and 20^th centuries was intrinsically connected to his own experiences as a German Jew, born in the Bavarian town of Fürth in 1923, who fled with his family to the United States and served in the US army during the Second World War.

Earlier this year I visited the memorial of Ahlem concentration camp outside the city of Hannover for a book I am writing on Kissinger’s early life. The site was suffocatingly small – just half the size of a football pitch – for the thousand or so prisoners confined to work in the asphalt mine located down the hill. Today, the brick outlines of the barracks flow under the fence and into suburban gardens. There was a school football pitch over to our right and houses loomed over us as we listened to the rabbi.

On 10 April 1945, the 84^th Infantry Division had drawn itself into an arc around the perimeter of Hannover. As the forces closed in, a small group of soldiers stopped on the roadside outside the village of Limmer. They caught the stench first; a shift in the wind brought the acrid odour of faeces, vomit and decaying bodies down the hill to the soldiers as they threw a baseball to each other. Up to their left, a group gesticulated, bellowed, and jumped up and down. In a cacophony of Polish and German, they pleaded with the soldiers to come closer. ‘We are prisoners! Jews! Jews!’

Kissinger drove up to the gates of Ahlem with his commanding officer. The soldiers tried to give the prisoners food, but their stomachs couldn’t metabolise the fat and some died. Kissinger spoke to a young Jewish prisoner: ‘You are free now.’ The meaning of the words seemed so meaningless as he uttered them. ‘I haven’t lived in filth and squalor,’ he thought, ‘I haven’t been beaten and kicked. What kind of freedom can I offer?’

‘That is humanity in the 20th century.’ Kissinger had fled Germany seven years before and now, in the grounds of Ahlem, he was witnessing the full horrors of the Holocaust. This ‘stupor of suffering’ had erased the boundary between freedom and imprisonment, movement and stasis, life and death. Kissinger wondered, ‘who is dead and who is alive, the man whose agonised face stares at me from the cot’ in the barracks, or the prisoner, ‘who stands with bowed head and emaciated body?’

Kissinger was only 21 at the time of the liberation of Ahlem. ‘But age in our generation is not measured in years’, he had once written as a young, lonely refugee in New York, ‘experiences are our standard, fate our criterions.’ The experiences of flight, war and the Holocaust formed the foundation of Kissinger’s attachment to international order and his antipathy towards instability. The Second World War marked a caesura between historical epochs, when civilisation’s end was predicted and humanity’s malignant capacities fully exposed. ‘The generation of Buchenwalde [sic] and the Siberian labor-camps can not talk with the same optimism as its fathers’, Kissinger wrote in his undergraduate thesis.

That visceral fear endured in Kissinger’s worldview through his work as a scholar and policymaker. The malignancy of the camps and the potential of nuclear weapons were a spectre over American power in the Cold War. ‘Our generation has succeeded in stealing the fire of the gods’, he wrote in Nuclear Weapons and Foreign Policy, ‘it is doomed to live with the horror of its achievement.’ The horrors of the Holocaust and the atomic bomb were the fulcrum of modernity, dividing it from a more innocent past. Order had to be ensured in politics through an effective balance of power among the strongest states.

As John Lewis Gaddis wrote, ‘to seek stability and sustain it in a chaotic world, even if temporarily, was for Kissinger as close as historical figures ever come to heroic achievement’. Kissinger’s most consequential act as national security advisor and secretary of state, the establishment of diplomatic relations with the People’s Republic of China following an extended period of isolation lasting nearly 25 years, was a goal motivated by such aspirations. ‘In the years ahead, the most profound challenge to American policy will be philosophical’, Kissinger wrote in 1969, ‘to develop some concept of order in a world which is bipolar militarily but multipolar politically.’ By engaging with China and incorporating it into the international community, President Richard Nixon and Kissinger, in part, sought to create a framework that could potentially prevent conflicts and enhance equilibrium among major powers in the global arena.

The fixation on international stability in Kissinger’s worldview also contributed to the controversial acts of his tenure in office. Criminality is a tedious subject for historians to have to adjudicate on; immorality is not. Reverence for Kissinger’s work on China and the Middle East should not exclude reckoning with the consequences of the Vietnam War or the Bangladeshi Liberation War. The argument that Kissinger possessed a deep understanding of the history and nature of intellectual politics cannot be refuted by pointing to the tragic casualties of American foreign policy; they should not be differentiated, for, ultimately, they occurred because of a fixation, by the US government, on great power politics over more minor nations or conflicts.

Kissinger disliked talking about his childhood experience in Nazi Germany or during the Second World War, but one can sense in his statements the immensity of their effects on him. In 2007 he spoke to a group of survivors of Ahlem. ‘That is when one saw the bestiality of the system and the degradation of human beings and there is nothing I am more proud of my service to this country than having been one of those who had the honour of liberating the Ahlem concentration camp.’ It was an untypically emotional speech from Kissinger, as he invited the survivors onto the stage. ‘And it is something we must not forget. It’s an obligation we all have. I don’t talk about it much, because people won’t understand it who haven’t been through it. But I salute the survivors here, and I’d be honoured if they came up here and had a picture taken with me.’

As I stood in the grounds of Ahlem, 78 years after the liberation, there were no survivors or liberators among us. Kissinger was the last living link to the camp.

History slips away so easily. Grandstanding debates about Kissinger’s legacy should not hide a deeper loss underway with the passage of time. In the course of researching my book, I interviewed a man from Fürth who, as a child, had watched the Führer speak from a train in 1935. Whipped up by Hitler’s speech, brownshirts stampeded through the town, trampling the young boy. He fled to the UK three years later, while the rest of his family were killed in the Holocaust. Kissinger and that man led very different lives, but they began in the same German town, members of the generation of Jews who were persecuted, expelled and murdered by the Nazis. We can venerate or decry Kissinger, but we also must reckon with the responsibilities of commemoration with which we are left.