On March 24, at the prime minister's home in Chequers, Margaret Thatcher conducted an afternoon seminar on Germany, its past, present and likely future. Six "experts" were invited; her foreign secretary and private secretary participated as well. The latter's confidential and distortingly compressed summary -- never distributed to the six of us -- was leaked to Der Spiegel and printed in the London paper The Independent on July 15, a few days after Mrs. Thatcher's closest cabinet ally, Peter Ridley, had published outrageous anti-German sentiments. His comments and the Chequers story together have created a fierce and continuing controversy in Britain and in Germany, with echoes in the United States. This has produced the opposite effect of what the six of us had hoped for: to contribute to a better understanding of a new situation in world history.

At Chequers I stressed that the Anglo-German estrangement and mutual distrust that began in the 1890s and that in two world wars developed into a deep hatred belong to the most important, indeed the most tragic, developments of our century. All the more important that at the time of Germany's sudden resurgence, old prejudices should not cause new harm. One must reckon with the relevance and the irrelevance of the German past in assessing the present and future.

There was much to rejoice in what had happened. At the end of November 1989 at a large meeting at Munich University I had said: "That we have seen a peaceful revolution -- perhaps the first one in the modern history of Europe -- is beyond doubt. We are witnesses of world-historical events ... that have filled more people with more hope than we have hitherto experienced in this century."

Especially the self-liberation of the German Democratic Republic and the desire for reunification must and should be welcomed. No one had envisioned this form of reunification: that the Poles and Hungarians, encouraged by a process inaugurated by a great Soviet reformer, should have been able to inspirit the citizens of the GDR to conduct a peaceful revolution. Not to see that as a cause for rejoicing would have been a denial of our common faith in freedom. This reunification was not prompted by a revived German nationalism but by the bankruptcy of a dictatorship.

By being optimistic about the future I am not in any way retracting my judgments of the German past. Perhaps it is precisely someone who for years has concerned himself with the earlier squandering of German power and German promise and with the multiple failures of the German elites who has the right and even the responsibility to welcome a new beginning and to warn Americans and Europeans not to endanger the future by memories of a past that has been overcome. That German politicians nevertheless have to reckon with these memories and respect them has been often enough acknowledged in the Federal Republic and by the new leadership of the GDR.

In April 1961 and in the summer of 1962 -- that is, both before and after the building of the Wall -- I had the good fortune to be able to work in the archives of the GDR. Ever since, I have had a special interest in the lives of the people of the GDR and a concern for their suffering. In a speech on June 17, 1987, before the West German Parliament on the day of national unity, commemorating the East German uprising of 1953, I said: "On this day we should honor the clear, courageous voices from the other German state that demand human dignity and human rights. These voices often come from the Church, a Church for which the teachings and the example of Dietrich Bonhoeffer are still very much alive ... " I still feel great admiration for individuals who fought for their freedom -- in uncertainty and anguish.

The march to unity came with extraordinary speed -- in consonance with the many events, surprising and unimaginable, that have characterized the last 12 months. The danger of a complete collapse of the GDR accelerated this process, but the Federal Republic recognized a uniquely favorable international constellation and deliberately steered toward a peaceful reunification -- in accord with West and East. A notable historic achievement!

Of course, this process -- this inevitable increase in German power -- has caused some unease abroad. Chancellor Helmut Kohl's initial hesitancies concerning the finality of the Oder-Neisse border between Germany and Poland served but to bolster this unease. It is all the more important to emphasize that we are dealing with a different Germany in a different Europe. As I said on June 17 before the Bundestag: "The history of the Federal Republic marks perhaps the most successful period in modern German history; in this history the return to Europe and the reconciliation with the West ... have played an essential role."

And yet: does the Federal Republic not face its greatest challenge now? These have to do with domestic and foreign concerns: What will happen to the people of the old GDR? How will the economic problems be solved, the property claims of West Germans adjudicated? And even more important, how will the long-afflicted people of the GDR be absorbed and assimilated? How will any form of psychological tutelage or West German triumphalism be avoided? How will respect and comprehension be shown precisely for those citizens who in October 1989 went into the streets, peaceful and yet uncertain of their own fate, under the unforgettable motto "We are the people"?

No sooner had Bismarck accomplished the great work of German unification when by launching the Kulturkampf (the struggle against the Catholic Church) he exacerbated old quarrels. Such inflammatory material does not exist today, but there are dangers of internal misunderstandings, of new anxieties and resentments.

But the Federal Republic -- in its enlarged form -- also faces new challenges in foreign policy. It did not seek this new power; it arose in part because of the collapse of the Russian Imperium and the weakening of American power due to domestic difficulties. The newly free Germany remain a member of NATO, itself in the throes of a deep transformation, but it also has special relations with the U.S.S.R., relations to be enshrined in treaty form next year. There are three power centers in the world today: Washington, Bonn and Moscow, with Tokyo remaining an isolated giant. How will this new weight of the Federal Republic affect its European policy? Will the German commitment to the European Communities remain unaffected by all these changes? Will the ''common European home'' -- invoked so often in earlier times by Mikhail Gorbachev -- have a German entrance hall?

Chancellor Kohl's visit in the Caucasus was a necessary prelude to German unity, and in many respects it represented a great victory for the Federal Republic and its Western allies. Still, even that visit aroused apprehensions. To what extent were the allies -- or at least the Americans -- informed ahead of time about the substance of the German-Soviet agreements? There are reliable indications that not everything had been agreed upon beforehand or anticipated by us. No doubt, the tone and the symbolic gestures of the meeting contributed to this unease. Was there not a touch of bilateralism, a hint of a unique German position within the Western alliance? Did it have to be in the Caucasus that Chancellor Kohl announced that on the day of German unification all Allied rights would automatically cease? In substance, all of this may have been unobjectionable, but tone and style have their own importance. And a certain unease is felt even in the United States -- in all the media.

The new Germany no longer has a Berlin problem; it no longer needs to be worried that other nations could interfere with German-German relations. The new Germany has gained the power to rid itself of most of the existing restraints; it has won room for maneuver. Only now appears the real challenge of statesmanship: How will the Federal Republic exercise its new power?

The self-liberation of Eastern Europe, the collapse of the Communist system and the renewed recognition of the virtues of the market economy has induced also in many Americans a certain sense of triumph. This feeling, however, is dampened by the sobering recognition that America's own economy and its social fabric have suffered considerably. Here -- and even more in Britain -- there is the occasional wistful recognition that the vanquished of yesterday are the victors of today.

But should we not rather have a certain confidence in our common future? Of course it is at first and above all that something quite rare has happened for Germany: it has received a second chance. This century ends as it began, with a Germany in ascendancy, based on its economy, its technology and its human capabilities. But now Germany and Europe together have a second chance: to secure their true values in peace and freedom, and under far more auspicious conditions than existed in the age of violent nationalism before 1914. Europe's murderous past should serve as admonition and encouragement to realize its peaceful promise.

The writer is Seth Low professor of history at Columbia. This article is abridged from one published in the Frankfurter Allgemeine Zeitung on July 26.