In his recent book Hitlers November 9, the German historian Joachim Riecker shows how deeply the memory of Germany's surrender in 1918 impregnated everything that Hitler did. He traces the origins of the Holocaust to Hitler's fury at the so-called November criminals who had allegedly betrayed the German nation, foremost among them the Jews. Hitler, as Riecker underscores, never believed that Germany had lost World War I. Instead, the Jews had engineered a betrayal. Hence Hitler's malignant obsession, to the very last day of his life, with eliminating the Jews who had cheated Germany of victory in 1918. Now, as the New York Times reports, Hitler's first anti-Semitic letter is headed toward the Wisenthal center in Los Angeles. Presumably, the letter is genuine—it was purchased for $150,000 from a private dealer. The tale of Hitler memorabilia, fake and real, probably deserves its own history.

The letter is known as the Gemlich Letter. Hitler was serving in the Reichswehr after World War I as an anti-Bolshevik agitator. Bavaria had been a hotbed of socialist and communist beliefs after the war and was briefly a socialist republic under the leadership of one Kurt Eisner. In fact, Germany itself was in revolt, which is why the army, fearful of chaos, prodded Kaiser Wilhelm to abdicate. This was a mistake. He fled to Holland by train, an ignominous flight if there ever was one. But Germany, a deeply patriarchal society, was left leaderless. It was not the last time that the army would make a spectacular political misjudgment. In fact, the army, probably more than any other institution, deserves the blame for Hitler's rise.

The army—specifically Capt. Karl Mayr, who soured on his quondam protege and later ended up dying in the Buchenwald concentration camp in 1945—tapped Hitler to speak to groups of soldiers and urged him to join the fledgling NSDAP. His oratorical skills came naturally; this was the great discovery. As Thomas Mann once observed, Hitler couldn't do much of anything—he couldn't drive a car, father a child, and so on. But the one thing he could do was rant. In his memoirs, Ernst "Putzi" Hanfstaengl recalls the mesmerizing effect that Hitler had from the outset. Somehow he was able to assimilate and spew forth the resentments and hatreds of an entire country, leading it into the abyss, from which it emerged after World War II, a true pariah among nations.

In the letter, addressed to one Adolf Gemlich, also engaged in propaganda work for the army, Hitler supplied what the Times calls "clarification" about "the Jewish Question." Hitler explained that the Jewish "race" had to be "removed" from Germany. This is important because it indicates that anti-Semitism was always at the core of his Weltanschauung. Some historians like to dispute this. In addition, there is much controversy about when the Final Solution was initiated. Was it a haphazard program, as some historians claim, or something that he planned all along. In addition, did Hitler become an anti-Semite during his days as a bum in Vienna? Or did he become one in Munich?

Now that the Holocaust has become history, such documents will assume an increasing importance, particularly in the face of the deniers who continue to proliferate in the Arab world (Mr. Ahmadinejad for one) and elsewhere. The document offers a reminder of the power of ideology to transcend mundane fact. And its tenacity.