Berlin in the autumn. No city in the world is more conscious of its history. Everywhere the ghosts flit past, always just outside one’s field of vision. Walking through the wet, glistening metropolis, street names saturated in significance pass by: Kochstrasse, where Checkpoint Charlie stood; Friedrichstrasse, where the visitor from the gaudy West emerged blinking into the monochrome microcosm of the East; the Russian Embassy on Unter den Linden, a vast, self-contained complex with accommodation and a school for its staff — the headquarters of what was the Soviet ruling power here for four decades.

As I pass, I notice a small plaque recording the fact that Heinrich Heine, the German-Jewish writer par excellence, once lived in a house on this site. There are the familiar monuments of Prussia, the Brandenburg Gate, and of Imperial Germany, the Reichstag, now post-modernised by Norman Foster. Unobtrusive by comparison is Mohrenstrasse, but for me this street has a special meaning: in a building there a press conference was held by Günter Schabowski on November 9, 1989. That press conference changed the course of German history — and my own.

As I arrive in mid-October, the country is already commencing a series of thirtieth-anniversary speeches and ceremonies, rising to a crescendo this month. It’s only five years since the last round. Some of my younger German friends think it’s more important to look to the future than dwell on the past. And yet it is so tempting for those who remember the heady days three decades ago to celebrate the most unambiguously positive event in modern history. Historians used to lament the failure of the abortive German revolutions of 1848 and 1918, blaming the rise of Hitler on these turning points that never turned.

Since 1989, though, the Germans have rejoiced in what has hitherto been known as die Wende, “the turning point”. It has now been renamed die Friedliche Revolution, “the Peaceful Revolution”: a phrase that has yet to catch on. Less bombastic but more flowery than England’s Glorious Revolution, Germany’s Peaceful Revolution has the same purpose: to evoke the lack of bloodshed, remarkable enough in any regime change, but especially so in one that has transformed national identity. Like the United Kingdom that emerged from the Glorious Revolution, the unified Germany that has emerged from the Peaceful Revolution is a very different country from the divided one that preceded it.

But how unified is Germany really? Though few now talk of Ossis (“Easties”) and Wessis (“Westies”), the Mauer im Kopf (“Wall in the head”) is still there. Antithetical identities forged in the Cold War have proved stubbornly resistant to Hegelian synthesis, to the “constitutional patriotism” that should — according to Jürgen Habermas, the philosopher who is to the Federal Republic what Hegel was to Prussia, — have emerged by now.

Much has been gained since unification — not least a new German confidence that others often, and wrongly, deride as the old German arrogance — but something was also lost. The Federal Republic today can no longer take refuge in the safety-first West German culture, created by Konrad Adenauer on the ruins of the Third Reich, securely anchored in Nato and dedicated to a European idea that never threatened to subsume its indubitably German identity. Adenauer’s original animated election ad, featuring his famous slogan “No experiments”, shows the “wise old man” (he was then in his late eighties but lasted another six years in office) manipulating levers and dials on the machinery of state, with the desirable products of “Peace” and “the Common Market” threatened by malevolent gremlins whose “experiments” end in the wailing of an air raid siren. The price of this “economic miracle” has been long periods of cosy Christian Democratic hegemony, with only two interludes of more reformist Social Democracy. But the economic miracle is now no less defunct than the wise old man and his allegiance to das Christliche Abendland, the “Christian West”.

Meanwhile, the reality of “the first socialist state on German soil” did not merely do away with private ownership but with privacy too. The surveillance state was spartan by necessity and proletarian by choice. After the Wall was built in 1961, the GDR became a time capsule where nothing changed, least of all the leadership. In this Stasi-stasis, where everyone spied on everyone else, trust simply vanished. For some Ossis, it has never returned. Fixated on an imaginary past of social justice and solidarity, they have succumbed to Ostalgie (nostalgia for the East). Outside the resurgent eastern cities, such as Leipzig, Dresden and of course Berlin, those who are dependent resent those who subsidise them; those who have remained behind resent those who left. The Ossis have become ossified in a culture of pessimism and a politics of hatred. Their cultural despair has crystallised into a populist party, the Alternative für Deutschland (AfD). Its rise signals the end of the post-1945 moratorium on the public expression of reactionary or revisionist attitudes to the past.

On the neo-Nazi fringe, paramilitaries plot revenge on Jews, Muslims and the liberal elites. While I was in Berlin, one of them chose Yom Kippur to assault a synagogue in Halle, live-streaming himself as he denied the Holocaust while trying to carry out his own, then using a 3D printed plastic gun to kill two passers-by. How many more such angry young men are lurking in small towns in East Germany?

This ossification of the Ossis is clear in a survey published recently by Die Zeit. The poll reveals that in the former East, 41 per cent believe that since the Wall came down, their ability to express their opinions has actually worsened. A majority is dissatisfied with the way democracy functions in the unified Germany; a larger majority thinks not enough notice is taken of the Ossis. Perhaps the most striking fact: 58 per cent believe that, compared to the GDR, legal protection against the arbitrary power of the state has either got worse (22 per cent) or hardly changed (36 per cent). The young are, in general, less disillusioned, but a large minority shares the attitudes of those who actually lived under the dictatorship.

Angela Merkel’s contemporaries have seemingly forgotten the Stasi, the absence of human or civil rights, even the Wall itself. Worse still: the older inhabitants of the GDR, the first generation there ever to live without fear of the nocturnal knock on the door by the secret police, have transmitted to younger generations both their nostalgia for their Kafkaesque past and their paranoia about the present.

None of the millennials I spoke to thought unification had failed, but all were worried about the East and its discontents

Thirty years after the opening of the Wall, then, the people who were liberated are now living in denial. Some in the West are so appalled that they wish the Wall could be rebuilt. Others, such as Armin Laschet, one of the candidates to succeed Mrs Merkel, advocate Westbau, reconstruction in the West, where infrastructure has been neglected — though this would inevitably deepen the East-West divide. There is regret among Western opinion-formers about their failure to inculcate democratic values in the aftermath of unification. “We lacked the confidence to do what the Americans and British did after the Nazi period,” observes one. “Maybe we should even have re-educated those who had never known freedom.”

So how do millennials in Berlin see Germany’s predicament? None that I spoke to thought that unification had failed, but all were worried about the East and its discontents. I meet Felice Maltzahn, 29, at a Vietnamese Lokal in Prenzlauer Berg, coolest of the former working-class districts of East Berlin. Her family had moved to Potsdam in 1994, going in the opposite direction to the mass migration from East to West. As the only Western girl in her primary school, she told me, she quickly learned to conform. To fit in with the rest of her class, she pretended that her parents were divorcing.

In the GDR, where the family was subordinated to the state, children were a luxury and divorce was the norm. (Mrs Merkel, who has had two husbands but no children, is not untypical.) Felice’s class teacher glamourised the Communist regime. Not until history lessons in her teens did she discover that it had been a police state. The lesson, for Felice, is that freedom cannot be taken for granted. Her response is clear: “We need a United States of Europe.” Together with friends from various countries, Felice has even founded a pan-European party, Volt Europa, two years ago. Now they have an MEP. It’s a start.

Philip Haibach, 28, had seldom given the East a thought until he moved to Berlin two years ago. Born after the Wall came down, he says he has lived through just one big geopolitical event: Brexit. It has left him feeling more European. Yet Philip is proud of his country, too, and what it has achieved: “I feel very German, but I’m a happy German. I don’t like what happened under the Nazis but I do like what it caused: that forward-thinking while reflecting on the past. I don’t feel guilty and I don’t want to, either.” He fears that far-right populism has made xenophobia, anti-Semitism and racism salonfähig (respectable) in the East. He still doesn’t feel at home there: when he ventures out of Berlin into the hinterland, his accent and attire instantly give him away as a Wessi. “My generation hates ‘irreversible’ and ‘unpredictable’,” Philip declares. “We like to try before we buy. But we face the future with confidence.”

There is something deeply sincere and impressive about this younger generation of Germans. Mathias Döpfner concurs. This giant of a man, a rare intellectual in business, is the head of Axel Springer, the eponymous group founded by postwar Germany’s leading media mogul, who created Germany’s biggest tabloid, Bild. The firm is still going strong: at a time when most newspaper publishers are still shedding staff, Döpfner has doubled his by investing in new media.

I visit him at the top of their 1960s skyscraper, soon to be replaced with a vast new building next door. “I am very hopeful for the generation aged between 16 and 30, or perhaps even 40,” he tells me. “I see there a good balance between idealism and pragmatism, a new realism about politics. This is where the new leadership will come from.” Döpfner is critical of the present German leadership, but refuses to see the future in apocalyptic terms. “Europe has a vital role, despite its weaknesses, in a world where America is increasingly isolationist and China is increasingly totalitarian.” He looks me in the eye. “And Europe needs the British contribution. Germany in particular needs the British. Do the British need the Germans? I’m not so sure, but I believe so.”

Brexit angst is apparent when I visit Die Welt, the paper founded by Springer to be the German equivalent of The Times. As a monument to his Anglophilia, Springer even bought the Georgian wood panelling from the old Times building to furnish his 19th-floor penthouse. Now known as the Journalisten-Club, Berlin’s homage to a London gentleman’s club is full of treasures and memorabilia, including a piece of the Wall signed on the spot by Kohl, Bush and Gorbachev. Die Welt’s morning editorial conference is presided over by Ulf Poschardt, the dynamic editor-in-chief. Poschardt made his name in the 1990s with a book on “DJ Culture”, followed by others on such themes as coolness, loneliness and he is now writing one on Mündigkeit (maturity).

His latest wheeze, he tells me, is a “Liberalism Rebellion” to counter Extinction Rebellion. Die Welt’s assembled editors greet me as an honorary colleague, before getting down to business. I’m especially delighted to encounter an old friend, the historian Michael Stürmer, who has now retired from academic life but still writes for the paper as its chief correspondent. At 81, Stürmer has not lost his saturnine good looks. “You and I are maturing together,” he tells me. After the conference, Poschardt explains his theory about Boris Johnson: “He is a product of punk. Look at his hair!” To my surprise, neither Poschardt nor Döpfner has ever met Boris, the first professional journalist to become prime minister — a grave oversight that I should like to rectify.

It’s reassuring, at least for a lifelong Germanophile, to encounter such Anglophilia among my counterparts in Berlin — although the angst, anger and even anguish at the prospect of being abandoned by the British is palpable. When Michael Gove spoke recently at the German Embassy, he was heckled for allegedly comparing Brexit to the fall of the Berlin Wall, thereby insulting his hosts. A Twitter squall soon subsided after it transpired that Gove had done no such thing. It is understandable that Germans are irked by any suggestion that the Wall, which was designed to keep people in, could even be mentioned in the same speech as Brexit, which will create a barrier to free movement across the Channel.

But is the mental divide that has long outlasted the physical one in Germany so incomparable to the one in Britain that the referendum revealed? Both are instances of the phenomenon that Disraeli described in Sybil: “Two nations; between whom there is no intercourse and no sympathy.” At about the same time, Heine was longing for an elusive unity that was more than skin deep: “A united Germany is what we need, united without and within.” Ossis und Wessis, Leavers and Remainers: do we not, as nations, share a similar plight?

For germans there has, of course, been one ecstatic and cathartic experience of national unity. I became fully aware of the unique place of der Mauerfall, the fall of the Wall, only last summer, when our daughter took us to the Reichstag to watch an open air son et lumière show depicting a century of German history for a huge audience of tourists. After the grim eras of war and dictatorship, we came to 9 November, 1989. As the background music rose to a climax, we saw footage of the famous Schabowski press conference. And suddenly there I was, a bespectacled young journalist, holding a microphone and blurting out a question which, perhaps because it was the first thought that came into my head, summed up what everyone else was thinking too.

How did I come to be there? I had woken up in the night with a strong feeling that I should be in Berlin. As I had spent two years in Germany as their correspondent, the Telegraph foreign desk let me go. I arrived only just in time. As a senior Berlin party official whose communism had a marginally more human face than that of the leader, Egon Krenz, Günter Schabowski was there as spokesman to report on a meeting of the Central Committee. It was only at 6.55 pm, five minutes before the long and hitherto tedious press conference was due to end, that an Italian journalist asked a question about travel.

After a certain amount of waffle, Schabowski abruptly announced that the party had decided to “make it possible for every citizen . . . to emigrate”. He then produced a paper and began to read it very fast. In a few sentences, he outlined a new travel regime, not only for “permanent departure” from the GDR but for private travel too. To say that the room was electrified would be an understatement. We could scarcely have been more dumbfounded if the Angel Gabriel had made the announcement. A flurry of questions now descended on Schabowski. One German journalist shouted out: “When does that [regulation] come into force?” Schabowski peered at the paper and replied: “Right away.” This was jumping the gun and not at all what had been planned by the Central Committee. Yet it proved to be crucial in determining how the story would be reported that evening, for it seemed to imply that East Germans could cross to the West immediately. More questions followed, including one about whether the new right to travel applied to West Berlin. Schabowski, by now conscious that he was in over his head, found to his surprise that this was indeed what his paper suggested.

Then it was my turn. Nobody had yet mentioned the Wall. Yet it was a matter of life and death to do so. This brutal regime had killed more than a hundred of its own citizens trying to cross the border since 1961, and a few weeks before had been preparing to massacre protesters in Leipzig — the “Chinese solution”. We had to know what would befall people who came to the checkpoints and demanded to be let through. Though the question I asked was mine, it was also the one to which millions of Germans, indeed the whole world, wanted an answer: “Herr Schabowski, was wird jetzt mit der Berliner Mauer geschehen?” (“What will happen with the Berlin Wall now?”).

Schabowski looked at me nonplussed. The hubbub of the press ceased. There was a silence that seemed to last forever. As the Harvard historian Mary Elise Sarotte puts it in her definitive book The Collapse: “It seemed as though Schabowski had suddenly lost the power of speech.” His reply, when it came, was to bring the interrogation to an end. “It has been drawn to my attention that it is 7pm. This is the last question, yes, please understand!” He bought time by repeating the question, then tried to deflect it by linking the status of the “fortified border” to disarmament negotiations, and finally left the question hanging in the air. His tactic didn’t work. A child could see that the regime had no answer: why would you have a wall through your capital city unless you wished to stop people crossing it? In that moment of truth, the Cold War ended.

The press conference had ended in confusion, but outside on that fine November night a trickle of very determined people arrived at the Bornholmer-Strasse checkpoint and demanded to be let through. They knew what they wanted and they just kept coming. No orders had been issued and the trickle became a flood. It was left to Lieutenant Colonel Harald Jäger to make a decision. After three hours, at 11.30pm, he let his people go.

The Peaceful Revolution happened. The Germans redeemed themselves. And my love affair with Germany has lasted to this day. Brexit notwithstanding, that love — sealed by the question to which the people gave their answer — will endure until my dying day.