Since the early days of Donald Trump’s presidency, there have been calls for criminal inquiries into everything from his dodgy tax returns to his 2016 campaign’s involvement with Russian intelligence. Over the past two years, as evidence of his and his administration’s wrongdoing have mounted, those calls have become more fervent. Vice President-elect Kamala D. Harris said in June 2019 that, were she president, her administration would prosecute Trump.

Yet Joe Biden won the presidency in no small part with an appeal to unity. Liberals fear that his bipartisan ethos might lead him to forgive and forget the Trump administration’s crimes, from bribery to obstruction of justice to routine violations of the Hatch Act. And we’ve been here before. In 2009, President Barack Obama declined to prosecute Bush administration officials for the commission of war crimes, torture in particular. Some commentators see a pattern of Republican abuse and Democratic forgiveness stretching back to Watergate and the Iran-contra scandal. If Trump and his associates are not prosecuted, they argue, it might set a devastating precedent. Others worry that the desire to prosecute Trump could amount to no more than “vengeance” that would further erode democratic norms. This vigorous debate on the left asks how we as a nation can get to the bottom of the Trump administration’s criminal behavior, while also ensuring that no future administration can act in such a manner again.

While there are critical differences between what this administration is suspected of doing and the violence committed by Nazi Germany, the commentariat often compares Trumpism to Nazism. It is no surprise, then, that some have referred to Germany’s denazification as a model for how the new president could deal with Trump and his administration. But those who use the comparison should recognize the mixed results of the German approach. The denazification process is widely considered to have been only partially successful — but it also underscores the importance of confronting painful and criminal pasts.

Almost 80 years ago, as World War II ground to its bloody conclusion, there was no talk of magnanimity. British Prime Minister Winston Churchill supported summary executions of high-ranking Nazis, as did Henry Morgenthau Jr., Franklin D. Roosevelt’s treasury secretary. But cooler heads in the American administration eventually prevailed, and on Aug. 8, 1945, three months after victory in Europe, the International Military Tribunal at Nuremberg was born.

This court, staffed by judges from each of the Allied Powers, tried high-ranking Nazis for war crimes, crimes against peace and crimes against humanity. Subsequently, the U.S. government staged 12 more trials at Nuremberg, each one dedicated to prosecuting a specific arm of the Nazi apparatus, such as judges, the military high command, medical doctors and so forth.

While these Nuremberg trials (famously captured on screen by Spencer Tracy and Marlene Dietrich in “Judgment at Nuremberg”) are still well-known, they were only the tip of the iceberg of Germany’s denazification. German courts tried thousands of lower-ranking Nazis and fellow travelers in the years after the war. Special denazification tribunals examined hundreds of thousands of Germans, determining whether they would be eligible to collect their pensions or continue to work. The processes of establishing the criminal nature of the Nazi regime, of prying ordinary Germans away from Nazi ideology, and of establishing democratic rule were undoubtedly the most far-reaching and ambitious in history.

Historians have assessed these efforts in different ways. On the one hand, the Nuremberg trials established a set of international criminal norms, in particular that international tribunals could punish genocide and other crimes against humanity. When special courts were created to prosecute perpetrators of genocide in Yugoslavia and Rwanda decades later, it was to the precedents of Nuremberg that they turned.

On the other hand, if denazification’s principle purpose was to convince ordinary Germans of the wrongness of Nazism, then it was at best a partial success. Although Germans initially expressed support for the Nuremberg trials, their enthusiasm quickly waned as it became clear that they, too, might be subject to prosecution. The idea of collective guilt was anathema. When West Germany was founded in 1949, many Germans did their best to forget the 12 years of Nazi rule.

Although many Germans had rejected denazification by 1949, those four years had given their country a chance to decouple their state and society from National Socialism. The processes begun by the Allied Powers confirmed that the Nazi Party had been a criminal organization and that (West) Germany would henceforth be a democratic state. Ultimately, the trials of former Nazis offered Germany’s politicians a chance to rethink German democracy and to place it on surer footing.

The process of confronting the Nazi era continued long after the Allied Occupation had ended. In the 1960s, young West Germans began questioning their parents about Nazism, forcing new reckonings with the past. Eventually, West Germany started trying former Nazis with more gusto, and its politicians began publicly atoning for the Holocaust and the destruction of World War II. In the decades since, Germany built on the legacy of Nuremberg, making its confrontation with the Nazi past a cornerstone of its national identity.

What can we learn from Germany’s rocky path of denazification? To state the obvious, the United States is not Nazi Germany. The Trump administration, for all that it has done, has not committed genocide or launched a transcontinental war of aggression. The crimes of Nazi Germany were of a different magnitude than those of President Trump. Nonetheless, the questions that confronted Germans in the 1940s and 1950s are parallel to those we confront today: how to make sure future governments never commit such crimes again — or worse.

The postwar German experience of denazification suggests a twofold approach. On the one hand, we must hold those who have committed crimes accountable, allowing justice free rein, even if its targets are the ex-president, his family or former Cabinet secretaries. Congressional inquiries, too, may serve a valuable role in uncovering wrongdoing and suggesting structural reforms. On the other hand, the Biden administration must be careful to avoid talk of collective guilt, for which there is no judicial remedy and which can serve only to alienate those who might yet return to the democratic fold.

We must also bear in mind that denazification was a process that took decades and was never truly complete. Trials for wrongdoers were a necessary component of staving off future calamity. But just as denazification provided only a basis for future democratic development, so would trials of Trump officials be only a starting point for the social and political reforms we so urgently need, reforms that will also require our politicians to confront this country’s legacy of racism with greater clarity than ever before. Like Germany in 1945, we have an opportunity to reimagine our society. The Biden administration should seize it.