NO ONE could doubt that, from head to toe, Ewald-Heinrich von Kleist was a military man. Generations of training, from the 12th century, had given him that straight Prussian spine and that cool, unswerving look. His ancestors, on the cold, undulating family estates on the Gulf of Riga and in Pomerania, had been Rittmeister, masters of cavalry. The good old days, it seemed to him, were when German men had been proud to wear their uniforms in the street. In person he was rarely off the defensive, civil but unexpansive, returning questions with a simple “You know the answer to that.”

In 1940, at 18, he abandoned his architectural studies and joined the Wehrmacht. He was in Infantry Regiment Nine, famous for the number of titled officers it contained. With eagle and swastika on his chest, he fought for three years round Lake Ladoga in Russia until he was invalided out. In 1944 he was on the eastern front again, fighting until the front had disintegrated to the city of Berlin itself. Yet between the first Russian stint and the second he twice agreed to carry enough explosives, and get near enough to Adolf Hitler, to kill him.

It was not, he said, the business of soldiers to think too much. Orders were orders. He worried later that Germany’s post-war Bundeswehr was being trained to be too gentle and thoughtful, to the point of uselessness. Nonetheless, his own soldiering was so bedevilled by thinking—to obey, or to remove, a criminal leader—that he was lucky to survive.

The questioning began at home, in Schloss Schmenzin, set in 3,000 hectares of Pomerania, where his father opposed Hitler to the limit of his strength. He resisted him as a Christian, a conservative and a monarchist. The Nazi flag never flew from the castle, and the Nazi salute was never given there. The only insignia his father tolerated was the white Maltese cross of the Order of Saint John (Brandenburg branch), of which he was made a knight of justice in 1935, ten years before he was guillotined for plotting against Hitler. He did not stop Ewald-Heinrich from enlisting. But then he knew that the seeds of resistance were sown in him already.

Amid the Russian snows as a very young company commander, Ewald-Heinrich found that he never got used to the deaths of his men. Increasingly, he wondered what they were dying for, in a war that was “pointless” and “wrong”. He was a proud German, devoted to the Fatherland, perhaps the more so because his family lands were so close to the edge that they were swallowed into post-war Latvia and Poland. But the words dulce et decorum est pro patria mori meant nothing to him now, when the state itself was murderous.

The one thing that seemed worth dying for was the erasing of Hitler from the scene. When Claus von Stauffenberg, leader of the anti-Nazi plotters, asked him to become a suicide-bomber early in 1944, he still hesitated, hoping that his father would object and save him. But his father paused for only a moment before he told him he must do it: “A man who doesn’t take such a chance will never again be happy in life.”

The path not taken

In the event, he never quite put his courage to the test. He agreed to wear two hand grenades under his uniform and to detonate them as he stood to attention before Hitler, but the Führer cancelled their meeting. Similarly, in the plot of July 20th 1944 to kill Hitler in the “Wolf’s Lair” in east Prussia, he agreed to carry the suitcase of explosives into the conference room but, in the end, was told to stay in Berlin. For a few hours, feeling history “bend on the edge of a knife”, he believed Hitler had been killed. In fact, he had survived. Five thousand were killed to avenge him; but Mr von Kleist, after brief imprisonment, was dismissed as a callow, apolitical soldier and sent to the front again. He was the last of the plotters to die, their youngest recruit.

As the war ended, he knew what his calling was. There must never again be such blood-letting unless the most vital interests of Germany and the West were involved. He began to encourage debate, setting up a publishing house for defence books and inviting Europeans and Americans to talk candidly together about what was worth fighting and dying for. Great names, among them Helmut Schmidt and Henry Kissinger, Donald Rumsfeld and Edward Teller, eagerly came to Munich every year from 1962 onwards to discuss security, and the transatlantic alliance was the stronger for it. Scorning pacifism, Mr von Kleist never invited Greens to the Munich Conferences; distrusting the too-vague notion of a war on terror, he disapproved of the deployments in Iraq and Afghanistan. Beyond that, though, he preferred to conceal his own opinions and his past.

Prussian reserve, some said: the same hauteur that made him refuse to help when Hollywood made a film about the plot of July 20th. Frustration, perhaps, that the plotters were often disparaged by the left as aristocratic, Christian and conservative—and, immediately after the war, were even called traitors. In 1944 he had simply done what he thought necessary and right, as both a moral man and a soldier under orders: defended his homeland against barbarian despoilers and low-class, law-breaking gangsters, as the von Kleists had done for generations before him.