Nuremberg, nestled in southern Germany, was painstakingly rebuilt after the Second World War. Most of the city center was flattened by Allied air attacks and most government buildings were destroyed. Most, that is, except Nuremberg's Palace of Justice. It was in the gray sandstone building that the Nazis had enacted notorious Race Laws years earlier. Those laws were later seen as a key step toward the mass murder of Jews and other minorities.

The Allied powers chose Nuremberg as the location of the trials for the city's symbolic importance to the Nazi rise to power, but also because it was one of the only courthouses in Germany that withstood the Allied air war.

Today, outside Nuremberg's Palace of Justice, there's no sign, no plaque, no hint of the historic experiment that took place inside nearly 60 years ago.

Nuremberg prosecutor Benjamin Ferencz recently returned to Courtroom 600 where he prosecuted one of the most shocking cases at Nuremberg. "I was the chief prosecutor against SS extermination troops that murdered over a million people in cold blood," says Ferencz.

The units—called the Einsatzgruppen—consisted of some 4,000 men who followed regular Germany army troops into conquered territory, usually in the Soviet Union. There they would round up Jews, gypsies and others, including Soviet Communist party officials. The prisoners would then be executed and their bodies dumped into pits.

These were not top Nazi leaders but elite military squads that conducted widespread killing. When the trial of the Einsatzgruppen opened in 1948, Benjamin Ferencz told the court: "The slaughter committed by these defendants was dictated not by military necessity but by that supreme perversion of thought, the Nazi theory of the master race."

In investigating the Nazi atrocities, researchers had discovered a massive archive in the Nazi foreign ministry in Berlin. The documents were a goldmine for prosecutors like Benjamin Ferencz. Among a wide range of material detailing Nazi extermination efforts were daily reports compiled by Einsatsgruppen commanders. "Every day," says Ferencz "they reported to Berlin which unit had entered which town, under the command of which officer and how many people they murdered in cold blood at that time. By taking an adding machine and adding up the numbers I reached a total of over a million people had been slaughtered that way by these special units."

The records themselves were so damning that Ferencz called no witnesses. In all, 24 of the Einsatzgruppen defendants were found guilty. Thirteen got a death sentence and the others were sentenced to long prison terms.

While death camp officers and execution squads were obvious candidates for any war crimes tribunal, American prosecutors, led by Justice Robert Jackson, had a more sweeping view of justice in mind. They saw the supreme crime at Nuremberg not in any specific act of Nazi mass killing, nor in the construction of the death camps like Auschwitz. For American prosecutors, the supreme crime was a completely new criminal charge: waging aggressive war, or the crime against peace.

At the opening of the first Nuremberg trial, Justice Jackson distinguished between legitimate defensive wars and aggressive wars like the Nazi conquests in Europe. Jackson said: "Any resort to (aggressive) war, any kind of war is a resort to means that are inherently criminal as means. War inevitably is a course of killings, assaults, deprivations of liberty and destruction of property."

Nuremberg was a first: prosecuting not only top leaders, but the inner workings of a country's war machine.

But Benjamin Ferencz says prosecutors knew that one trial of 21 Nazi leaders did not adequately address criminal guilt in Germany. "It was felt that we had to bring in the industrialists, who built the concentration camps in order to have cheap labor for their war machine. The generals, who had the power to stop Hitler and chose not to. The doctors, who conducted medical experiments for example, were to be portrayed so the world could see precisely how it was that a civilized country like Germany could resort to such barbarism. That was the purpose of the subsequent trials."

For William Caming, another American lawyer at Nuremberg who would help prosecute German diplomats and other government officials, the trials had another aim.

Caming says: "There was also the hope that the trials and the revelation of all of the acts would reeducate the German people who had lived under the yoke of Nazism since the early 30s."

Nearly 200 defendants were charged with crimes against humanity and other war crimes by American prosecutors at the subsequent Nuremberg trials. Among them, Germany's most prominent businessmen and professionals. Prosecutor Telford Taylor, who took over when Justice Robert Jackson returned to the Supreme Court, accused German industrialists of "manufacturing the turbines of war and the tools of holocaust" in their factories.

In his opening statement at the trial of German industrialists, Taylor said: "One does not build a stupendous war machine in a fit of passion. Or an Auschwitz factory during a passing spasm of brutality. There will be no mistaking the ruthless purposefulness with which the defendants marked on the course of conduct. That purpose was to turn the German nation into a military machine and build it into an engine of destruction so terrifyingly formidable that Germany could impose her will and dominion on Europe."

Among the accused were executives from the I.G. Farben company, a huge chemical firm that produced Zyklon-B, the poison gas used to kill millions of Jews at Auschwitz and other Nazi death camps. Farben also ran a synthetic rubber factory at Auschwitz with inmate labor. Carl Krauch, the company's top executive and other Farben managers were tried using the company's own documents which revealed Farben's deep involvement in the Nazi war effort. Historian Jonathan Bush says the Farben employees had a unwavering explanation for the work they did and the papers they signed.

"They said: 'We were made to do it,'" says Bush. "'We would be shot if we didn't.' So in a way they could do jujitsu with all the evidence: 'Yes he signed that, yes he said that…but you're reading it as if he meant it. He didn't mean it. He had to do that to survive.'"

The excuse did not work for Carl Krauch. He was found guilty and sentenced to prison. But of the 24 Farben employees on trial, 11 were acquitted. The judges accepted the defense by some Farben executives who claimed they acted under duress. That helped established a precedent that those who make the policy and give the orders to commit war crimes are more responsible than those who obey the commands.

If the trials were intended as a mirror for Germans to better see Nazi crimes, the Germans themselves didn't like the view. Jonathan Bush says the prosecution of soldiers and industrialists was controversial in Germany and the United States.

"The analogy to many western observers was to Henry Ford," says Bush. "These industrialists— they're successful businessmen, they're doing what their country's laws allow them to do. They are operating within the law, for their country, in a time of war. "

While the trials were meant to provoke soul-searching among the Germans, American prosecutors also knew their work would shape the future of international justice. That preoccupied Benjamin Ferencz, who prosecuted the Nazi death squad members.

"The question I had in my own mind was, "What do I ask for?," says Ferencz. "Do I ask the tribunal to hang them all, chop them up into a million pieces or something like that? I felt, no, that wouldn't really serve a significant purpose because you never could balance their 22 lives against the millions who had been slaughtered. And if I could develop a rule of law that could protect human kind in the future, that would be significant."

Nuremberg would establish a body of jurisprudence that would lay the foundations for what is now understood as human rights—the Genocide and Geneva Conventions—as well as for ad hoc UN tribunals established in the early 1990s and the permanent International Criminal Court. But before the Nuremberg prosecutions were even complete, the court's effectiveness began to erode in a new tide of international politics.

The Second World War gave way to the Cold War, and in June 1948, Soviet troops blockaded Berlin, which sat deep in the East German territory they controlled. America and its western allies responded with a massive airlift of supplies into beleaguered West Berlin. Even prior to the Berlin airlift, America started to see West Germany as a potentially powerful ally against the Soviet Union.

Caming says: "We had visits from congressmen and senators who favored the re-armament of Germany and who said that we had to get rid of the trials because they're an obstacle."

An obstacle because German political and military leaders wanted the Nuremberg trials shut down and the prisoners released before agreeing to side completely with the U.S. At the same time, some politicians stepped up criticism of the trials themselves as unfair. Some went so far as attacking individual prosecutors.

Belle and William Zeck met as lawyers in Nuremberg and were later married. Both the Zecks worked on the prosecution of I.G. Farben executives. The trials of German industrialists, which included the confiscation of their wealth and property, was seen by some conservative politicians as a left-wing, even communist conspiracy.

Belle Zeck, who is Jewish, remembers several U.S. congressmen, including a young Wisconsin senator named Joseph McCarthy, who openly defended the German industrialists, and attacked the American tribunal.

At one point Belle Zeck was denounced as a communist on the floor of the U.S. House by Congressman George Dondero from Michigan.

Historian Peter Maguire, author of Law and War: An American Story, says criticism of Nuremberg in the United States was led by isolationist politicians, many of whom had opposed America joining the war against.

"They were basically saying that there were a handful of leftwing new-deal lawyers—even German Jewish nationals—which they would call recently immigrated American citizens running amok in the name of the United States in Nuremberg sowing seeds of dissension amongst our new allies, who would bolster the western front from the Red Army," says Maguire.

But Maguire notes that it wasn't just American isolationists who opposed Nuremberg. Supreme Court Justice William O. Douglas described the trials as legally unprincipled, while George Kennan dismissed efforts to re-educate Germans and said the entire tribunal should be terminated.

Amidst the criticism and red baiting, the subsequent American trials at Nuremberg concluded in 1949 with some 142 convictions. Twenty four Germans were sentenced to death and many others got prison terms. But they would not stay behind bars long. To appease West German leaders, American diplomats in command of the U.S. occupation zone formed a review board to consider clemencies.

The man who appointed the review board, John McCloy, stressed that the board was not reconsidering judgments but would examine fairness in sentences imposed by the tribunal. Many prosecutors suspected that politics were involved, though John McCloy always denied that he was acting on any political directives from Washington, according to prosecutors and historians.

"Between 1949 and 1958," says William Caming, "all of the prisoners had sentences reduced and were then released. Including, surprisingly enough, four of the leaders of the Einsatzgruppen death squads. It was a political measure. No members of the prosecution staff and none of the judges at Nuremberg were even consulted."

Among the first released were the German industrialists, including Alfred Krupp and Karl Krauch, the I.G. Farben executive. Many of the former prisoners, like Krupp, would re-establish their wealth and positions in German society. Years later, a handful of the convicted war criminals would be tried again in a series of war crimes trials in Germany that continue to this day. The German government and German industry also paid out billions of dollars in compensation to victims of Nazi crimes. And beginning in the 1960s, a post-war generation of German writers, intellectuals and politicians confronted many of the demons of Nazism.

According to historian Peter Maguire, others released early included 20 of the 24 Einsatzgruppen officers convicted by Benjamin Ferencz—including nine of those originally sentenced to death. The last two left Landsberg prison in 1958. Recently declassified U.S. documents and CIA files obtained by Maguire suggest that at least two former Einsatzgruppen officers later may have worked as spies for western intelligence agencies, including the CIA.

Human rights activists say the legal principles established at Nuremberg such as the crime of committing aggressive warfare and the concept of command responsibility were far more important than who got out of jail and when they were released.

With the establishment of a permanent International Criminal Court (ICC) in 2002, Nuremberg prosecutors like Benjamin Ferencz say the true promise of Nuremberg is only now coming to fruition.

Ferencz, who is now 82, was on hand at the United Nations headquarters in New York earlier this year when 66 countries ratified the treaty establishing the ICC.

Ferencz was in buoyant spirits when he mounted the podium with UN officials and other diplomats to mark the ICC's founding. "We were building on the Nuremberg foundation, which was to condemn aggression as the most serious war crime in the world because it is during time of war, all the other crimes are committed," Ferencz says. "To condemn genocide, to condemn crimes against humanity, those were the great precedents established at Nuremberg, and then affirmed by the UN and then of course the world went back to killing as usual."

One nation was conspicuously absent from the UN ceremony this year: The United States. The country that played such a central role in the Nuremberg trials opposes the new International Criminal Court. The Bush administration says that no American soldier should ever face trial in anything but a U.S. court.

Benjamin Ferencz strongly disagrees: "What the United States is saying is that we don't want the rule of law. I think that is dangerous, very dangerous. Because we cannot lay down a law for the United States and not for the rest of the world. That doesn't fly. Justice Jackson made that clear at Nuremberg. Law must apply to everyone equally or it's not law at all. Those who are pushing the other view have a misguided idea of what law is all about. They also have a misguided conception of how to safeguard the welfare and justice and rights for citizens everywhere."