The Ratz fan club site is down, but here is what it says on the topic:
Was Cardinal Ratzinger a Nazi?
Good grief. No, Virginia, Cardinal Ratzinger was not a Nazi.
The Ratzinger Fan Club normally doesn’t indulge in the muck and mire of such rumors, but you’d be suprised how many people write inquiring about this malicious rumor.
The story that Ratzinger was a member of the Hitler Youth is true. It’s a biographical fact that seems to have circulated on many a mailing list, and seems to surface at precisely opportune times when the Prefect finds himself in the media’s spotlight. From the way it has been presented, one might assume this is one of those skeletons the Cardinal keeps tucked away in his closet (next to his executioner’s axe and the token heads of Hans Kung, Matthew Fox, Leonardo Boff & Charles Curran).
The truth is that as Ratzinger mentions himself in Milestones: Memoirs: 1927 – 1977, he and his brother George were both enrolled in the Hitler Youth (at a time when membership was compulsory), and discusses family life under the Third Reich in chapters 2-4 of his autobiography.
Likewise, John Allen Jr., journalist for the National Catholic Reporter and author of 2002’s biography of the Cardinal The Vatican’s Enforcer of the Faith, — supplies the historical details sorely lacking in one of his many articles on the Cardinal:
As a seminarian, he was briefly enrolled in the Hitler Youth in the early 1940s, though he was never a member of the Nazi party. In 1943 he was conscripted into an antiaircraft unit guarding a BMW plant outside Munich. Later Ratzinger was sent to Austria’s border with Hungary to erect tank traps. After being shipped back to Bavaria, he deserted. When the war ended, he was an American prisoner of war.
Under Hitler, Ratzinger says he watched the Nazis twist and distort the truth. Their lies about Jews, about genetics, were more than academic exercises. People died by the millions because of them. The church’s service to society, Ratzinger concluded, is to stand for absolute truths that function as boundary markers: Move about within these limits, but outside them lies disaster.
Later reflection on the Nazi experience also left Ratzinger with a conviction that theology must either bind itself to the church, with its creed and teaching authority, or it becomes the plaything of outside forces — the state in a totalitarian system or secular culture in Western liberal democracies. In a widely noted 1986 lecture in Toronto, Ratzinger put it this way: “A church without theology impoverishes and blinds, while a churchless theology melts away into caprice.” *