FIFTY YEARS AGO today, Paul von Hindenburg, the president of the German Republic, appointed Adolf Hitler as chancellor.

For the next 12 years, Germany and the world were to live with the consequences of Hindenburg's decision. But even Hitler's suicide in 1945 was not the end of those consequences.

If greatness can be understood as impact on contemporaries and posterity, Hindenburg's decision was unquestionably among the "great" ones of our time, and Hitler himself claims an undeniable place among the "great" historical figures.

For better or for worse, to this day, the world's economic order, the attitudes of its superpowers, the peacefulness of Europe, the strife in the Middle East and our very vision of morality are among his legacies.

Like many another "great" move, Hindenburg's was not meant to work the way it did. Hitler was not supposed to achieve any real power. The rationale for the appointment of a 44-year-old former Bavarian corporal as head of government was a combination of political bankruptcy, tactical cunning and authentic constitutional crisis.

In January 1933, 36 percent of German wage and salary earners -- 7 million people -- were unemployed. Production had fallen to half of its 1929 level. Regular parliamentary government had collapsed in 1930, three years before.

Hitler and his National Socialists made hay among the casualties. In 1928 they had polled 2.6 percent in parliamentary elections. They scored 18.3 percent a little more than two years later, and peaked at 37.3 percent in July 1932. But new elections in November 1932 actually reduced their total to 33.1 percent, an absolute loss of about 2 million votes. By the end of the year, the Nazi Party's disintegration was a real possibility.

Hitler's amazing turn of fortune has less to do with Hindenburg, let alone with the voters, than with Franz von Papen, whose own short-lived government had been dumped conclusively only a few months before. Papen, a favorite of Hindenburg's, was panting for a return to office, and Hitler was to be his vehicle. Hitler's price for participation in the new government was the chancellorship. But Papen was vice chancellor, and an entourage of conservative camp followers assured Hindenburg that Hitler's Nazis would be contained. After all, Hitler included, the Nazis held only three portfolios in the new cabinet of 11.

But that evening, there was an enormous torchlight parade through Berlin's government district. As Hindenburg and Hitler looked on, as many as 100,000 marchers interchangeably sang the "Horst Wessel," their party hymn, and "Deutschland uber alles," the national anthem.

The episode defies replication in American terms. But a vast parade of torchlight marchers on Pennsylvania Avenue, many of them in sheets and interchangeably singing "Dixie" and "The Star-Spangled Banner" as they celebrated the presidential inauguration of a former Confederate corporal 15 years after the Civil War, would be at least a remote approximation.

It is hard to read contemporary news stories today without feelings of irony and humility. "The composition of the cabinet leaves Herr Hitler no scope for gratification of any dictatorial ambition," wrote Guido Enderis, The New York Times' correspondent in Berlin. Gustav Stolper, one of the best-informed journalists in Germany, argued that the real crisis would come later when the internal contradictions of the new cabinet stalled economic recovery, and it lapsed either into inactivity or counterproductive experiments.

Of course, a few months later, the January cabinet was a memory. The communists were proscribed, civil liberties were suspended, the parliamentary parties were dissolved, the unions had been liquidated, state governments and the army had been coopted, and the civil service had been purged, virtually without resistance. By the end of 1941, Hitler's Germany dominated Europe from the Pyrenees to the gates of Leningrad and Moscow.

The extraordinary rise -- and equally extraordinary fall -- of Hitler's Germany reverberate in the way our world works to this day.

On the face of it, the Hitler regime was an unbroken march from triumph to triumph: political stability, unilateral rearmament, restored national purpose, spectacular diplomatic successes. The political achievement was subsumed within an economic one that apparently satisfied not only business, industry and agriculture, but even labor.

Less than two years after Hitler took power, Germany's unemployment rate had been cut by more than half, the fastest recovery in the industrial world. By 1938, when an estimated 8 million to 11 million Americans were still jobless, Germans were struggling with an overheated economy and a seller's market for skilled labor.

Thus, while terror obviously was a deterrent to domestic resistance to Hitler, Nazi successes were at least as tangible a constraint. Martyrdom seemed hard to justify where no one was likely to notice or understand opposition to Hitler, and foreign governments avoided confrontation until it was finally thrust upon them.

On the other hand, success required continual reaffirmation. Thus, even the extraordinary impact on Germans of the blitzkrieg victories of 1939-41 wilted into cynicism and disaffection as it became apparent that Hitler won battles, not the war.

The churches, only rarely heroic, never quite capitulated either. Traditional political habits -- conservative, socialist, Catholic -- surfaced incrementally as the war continued and, by early 1942, as many as 100,000 were interned in domestic concentration camps.

Thus it was that Allied forces, entering Germany in 1945 with prewar newsreels in their memories of German masses thundering "Heil Hitler!", were both perplexed and cynical that there seemed to be no Nazis. Germans, on the other hand, were often puzzled that liberating armies insisted on acting like occupiers.

But there was actually some objective basis for the confusion. The denazification process was already underway as the war progressed. Last-ditch resistance never materialized. A fanaticized, nazified youth was a myth. What most Germans wanted, the Swiss journalist Fritz Rene Allemann discovered to his surprise on his first postwar trip to Germany in the summer of 1945, was neither revolution nor revenge.

All they wanted was an uneventful private life.

And so, at appalling cost and in ways neither he nor Hindenburg ever envisaged, Hitler actually solved the German problem, or even several different German problems, that had baffled Europe for at least a century.

The unreconstructed agrarian fiefdoms of the Prussian gentry, the industrial baronies of the Ruhr, the iron mystique of army and general staff, the sweaty romanticism of "Deutschland uber alles" -- Germany over all -- all of them were buried in the ruins. What was left were West Germany, East Germany and Austria, three more or less middle-sized states, two of them functionally and unself- consciously democratic, all of them integrated in larger international systems.

The anschluse or annexation of Hitler's native Austria by Germany into one united German-speaking realm -- that century-old haunt of Central European imagination -- is as remote today as the Crimeam war. The Europe Hitler proposed to save from both Western capitalism and Soviet communism is effectively divided between them.

German hegemomy, at last, is neither a possibility nor an issue. Largely because of Hitler, the superheated nationalism that once smoldered and intermittently flared in Europe's heart now survives only at such outer edges as Ireland, Cyprus or the Falkland Islands. Hitler thought that World War II would be the last Franco-German war after centuries of allegedly "hereditary" enmity, but doubtless he never imagined it would work like this.

Without reference to Hitler, the behavior of the superpower legatees is virtually inexplicable. The 20 million and more Soviet war dead continue to haunt the Kremlin's aged oligarchs in a way that America's 290,000 combined casualties against Germany and Japan have never begun to affect Americans.

For policymakers in Moscow, the Soviet presence in East Germany and the Soviet empire in Eastern Europe are not only a form of reparations, but a lesson of history. The Poles, Czechs and Hungarians, not to mention the East Germans, share the liability.

What Americans internalized was the apparent lesson of the prewar years when Hitler grew great on the feckless indecision of his neighbors. Neither of America's two post- World War II wars is quite understandable without appreciation of how fear of "appeasement" governed both the official and the public mind for a generation.

Even today, when "no more Vietnams" holds the balance, the foreign and defense policies of the current administration can be understood at least in part as a quest for the simplicity, strength and innocent righteousness of the war against Hitler.

But Hitler's legacy hardly stops there. It arguably includes postwar France's ungraceful exit from Vietnam and Algeria as generals and politicians strove to make good the humiliations of appeasement, defeat and occupation. It includes Britain's end as a global power, and thus the shape of the modern Middle East.

If World War I was a giant step toward Arab independence and Jewish statehood, World War II was their culmination. The Nazi murder of 6 million Jews, and the inescapable urgency of resettling the survivors, were probably the most powerful arguments for the partition of Palestine in 1947 and Israeli statehood in 1948.

It is also hard to overemphasize Hitler's impact on Menachem Begin, Israel's prime minister, just as it is hard to overlook his impact on the Palestinians.

It is not only that the Jewish settlement and self-determination -- which led directly and indirectly to the Palestinian tragedy -- derived at least indirect legitimation from Hitler's persecution. In addition, Haj Amin el-Husseini, the grand mufti of Jerusalem and the dominant figure in Palestinian nationalism, compromised his cause in the eyes of the victorious British and Americans by his liaison with Hitler and wartime residence in Berlin.

The mufti's disgrace left the Palestinians without a credible leadership that might at least have limited the damage that led to 700,000 Arab refugees from the war that followed partition. Not only the Jewish state, but in some degree the Palestinian diaspora, is part of Hitler's legacy.

The world's social and economic institutions -- now under challenge from the severest global recession since the one that helped bring Hitler to power 50 years ago -- are more of the ripples from Hindenburg's fateful decision to appoint Hitler. The whole apparatus of postwar economic buffers -- the General Agreement on Tariffs and Trade, the International Monetary Fund, the World Bank -- testifies to the belated recognition that all nations paid a terrible price for the economic nationalism of the '30s.

The ubiquitous postwar welfare state finally acknowledged the explosive and corrosive political consequences of unemployment. The message unexpectedly seems as timely today as it was in 1933.

Even the doomsday technologies that seemingly make our world so different owe their origins to Hitler. The atomic bomb was built out of fear that the Germans would do it first. The intercontinental missile that carries it originated because the Germans chose instead to give priority to the rocket.

But the most pervasive, if intangible, part of Hitler's legacy is moral. The great ideas of the European Enlightenment, the truths the founding generation of Americans held to be self-evident -- not only life, liberty and the pursuit of happiness, but reason, goodness and human perfectibility -- only barely survived World War I and its terrible after- shocks, Verdun and the Somme, the slaughter of the Armenians and the civil war in Russia. It is vs viery hard to believe in human perfectibility since Hitler.

All of us who have come to consciousness in the last 50 years live in the shadow of certain discoveries about human nature few of us would ever have wished to share. "For us, the post-Nazi era will never be over," West Germany's Chancellor Helmut Schmidt told the Bundestag in 1979 on the 40th anniversary of Germany's invasion of Poland that started World War II. He was addressing his fellow citizens, the majority of them born long after Hitler's death.

But the proposition is true for all of us. "Si monumentum requiris, circumspice," the British historian Alan Bullock concluded his biography of Hitler. "If you seek his monument, look around."