Joseph Ratzinger arrived at Tübingen [University] in 1966, still enthusiastic about the promise of Vatican II and ready to take his place alongside the other budding superstars of German theology, especially Hans Küng on the Catholic side and Jürgen Moltmann on the Evangelical. Küng was serving as dean of the Catholic theology faculty when the chair in dogmatics came open, and he took the unusual step of not forming a, or list of three possibilities, to fill the position. He made Ratzinger his only suggestion, after phoning him in Münster to be sure he would accept. The faculty consented.

Küng and Ratzinger by all accounts got on very well during the Tübingen years. They had a standing dinner engagement every Thursday night to discuss a journal they edited together, making Küng the only colleague with whom Ratzinger socialized on a regular basis. They were a study in contrasts, Küng zooming around town in his Alfa-Romeo while Ratzinger peddled his bicycle wearing his professor's beret; but they seemed to connect.

Küng's increasingly progressive theological instincts, however, did not sit well with Ratzinger. By 1969, when Ratzinger departed Tübingen for Regensburg, the essentials of his more pessimistic, conservative outlook were in place. The events of 1968 had a strong bearing on this shift, and thus to understand Ratzinger's development it is important to take a deeper look at those fateful few months.

Several larger forces left the "baby boom" generation in Germany especially disposed to social protest in the late 1960s. First was the legacy of National Socialism. In the drive for reconstruction after the war, uncomfortable questions about who did what under the Nazis were largely shunted aside. Two decades later, however, children of university age began to ask their parents what they did under Hitler. Often they found the answers unsatisfactory. This indictment was crystallized in 1968, when Nazi hunter Beate Klarsfeld slapped West German Chancellor Kurt Georg Kiesinger across the face in a public protest of Kiesinger's Nazi past. Kiesinger had been a go-between during the war for Joseph Göbbels, Hitler's propaganda chief, and army head Joachim von Ribbentrop.

In addition, in Germany as in the United States, the boomer generation was enormous, adding millions of adolescents and young adults to the national population. The educational system was unequipped to handle the surge. The student-teacher ratio in German universities in the late 1960s was three times as high as in the United States, and four times as high as in England. At the same time, German youth were demanding that the universities become less exclusive. As late as 1968, only seven percent of German youth qualified for a university-level education, and only three percent actually enrolled. Thus at the same time that the numbers of the traditionally college-bound were growing, there was also pressure to expand the student pool. Under the strain, university services broke down in many places, creating a general mood of frustration. The student-teacher relationship was also a contentious issue. Student activists described the relationship in Germany as resembling that of a feudal lord to his serfs; there was an almost unbridgeable gap between the lordly professor and the lowly students. This, too, sparked outrage in a generation already disposed to question the integrity of its elders.

The question of violence hung in the air during these days of protest, though the student leadership in Germany never embraced it. In fact, most of the actual violence that occurred was instigated by the police. Nevertheless, the theory and language of violent revolution was tossed around a great deal among the students and their leftist sympathizers, enough to seriously alarm a large cross-section of Germans who lived only a few miles from an actual Communist state. As bombing and terrorist actions accelerated, this climate of alarm deepened.

Although the nerve center of the student movement in Germany was the Free University in Berlin, it gripped Tübingen as well. In a 1996 essay in the Sudddeutsche Zeitung, a 1960s student radical named Klaus Podak reflected on the spirit at Tübingen in the days after a student named Benno Ohnesorg was shot in Berlin during a protest over a visit by the Shah of Iran, triggering a massive wave of uprisings on campuses across the country: "The revolution was approaching. Its wild, hot air reached Tübingen like a breeze. Our cheeks turned red. Our hearts beat faster. Our eyes shone. Our bodies trembled. We were excited, day and night." At around the same time, another radical named Günther Maschke became editor of a student magazine in Tübingen and turned it into a leading organ of the protest movement.

Tübingen became the intellectual Mecca of the radicals, however, mostly because Ernst Bloch was there. Widely seen as the father of the 1968 student movement, Bloch's Marxist analysis of Christianity and social change provided much of the intellectual architecture for the radicals, and he personally offered support for their protests. At one point, radicals spray-painted "Ernst Bloch University" over the Tübingen sign on the campus's old assembly hall. In Milestones, Ratzinger testily acknowledges Bloch's influence, saying in passing that Bloch "made Heidegger contemptible for being petty bourgeois."

Bloch was echoed by Moltmann, who developed the idea of Christian support for social revolution in his "theology of hope" (Moltmann's language reflects the influence of Bloch's masterwork, Principle of Hope). The Tübingen New Testament exegete Ernst Käsemann likewise lent his support to students who charged that the church had too often participated in the capitalist exploitation of the poor; and traditional theology frequently served the purpose of propping up the system. Käsemann, though no radical, had a keen sense of political responsibility; his daughter Elisabeth had been murdered on account of her political activity by the military junta in Argentina.

For Ratzinger, all this was simply too much. Frustrated that the theology faculties were emerging as the ideological center of the protest movement, Ratzinger joined forces with two Protestant colleagues, Ulrich Wickert and Wolfgang Beyerhaus, to "bear witness to our common faith in the living God and in Christ, the incarnate word," which the three men believed was under threat. Ratzinger found himself in conflict with many of his colleagues. "I did not want to be always forced into the contra position," he said, and thus he abandoned Tübingen, a height that most theologians can only dream of attaining, after only three years.

Ratzinger left Tübingen for a regional institution that had none of its tradition. Regensburg was a brand new creation of the Bavarian state. It was as if a senior editor at the New York Times left at the height of his career to start up a small regional newspaper in Albany. Such a decision cannot simply be explained by differing intellectual outlooks, which are, after all, the lifeblood of a great university.

It has long been rumored that one factor in Ratzinger's decision to exit Tübingen was increasing personal hostility directed at him by students. Yet he says in Milestones, "I never had difficulties with students. On the contrary, I was able to continue speaking to a lecture hall full of attentive listeners." He has specifically denied a rumor that his microphone was once snatched away from him by a hostile group of students, though the incident was reported in the German press.

Although Ratzinger did continue to be a popular teacher, he experienced strident opposition from some students and junior colleagues. It expressed itself in disturbances in Ratzinger's classes. Küng says Ratzinger, like several other popular professors, including himself, had been targeted for sit-ins by leftist students. "They came in and occupied the pulpits," Küng said. "Even for a strong personality like me this was unpleasant," Küng said. "For someone timid like Ratzinger, it was horrifying." Küng said that he cancelled his own lectures at the end of the semester in 1968 because he was tired of having them "invaded," and he said he and Ratzinger exchanged complaints about the experience. Küng said he also heard rumors during this time that Ratzinger's graduate students were unhappy with him, but he was "not very much interested in the details."

In Salt of the Earth, Ratzinger said his problems were not with students but with the "non-professorial staff." These would have been the so-called "academic middle structure," assistants to professors-equivalent to adjunct professors in the United States. On German university campuses, these were among the most aggrieved sectors, as they spent some of their most potentially productive years writing book reviews and running errands for professors. Their ordeal ended only when, and if, they too were admitted to the guild. Joined sometimes by graduate students, they often formed a second avant garde of campus unrest.

Ratzinger was also deeply disturbed by events at the student parish in Tübingen, where a group of radicals claimed the right to express a "political mandate" for the parish. These students wanted to appoint the chaplain themselves and to lead the parish into political activism. The debate deeply polarized the Catholic students at Tübingen. Ratzinger expressed his worries about the situation to his students, especially on the question of the bishop's right to appoint chaplains. It was another awakening experience for Ratzinger, an object lesson in the dangers of a politicized faith.

Ratzinger later said the Tübingen experience showed him "an instrumentalization by ideologies that were tyrannical, brutal, and cruel. That experience made it clear to me that the abuse of the faith had to be resisted precisely if one wanted to uphold the will of the council.... I did see how real tyranny was exercised, even in brutal forms.anyone who wanted to remain a progressive in this context had to give up his integrity." According to observers who were at Tübingen in the late 1960s, several of Ratzinger's graduate students, including some who had followed him from Bonn and Münster, became puzzled and frustrated at his new stance. Some deserted him to study under Küng or Metz.

The other revolution of 1968, which also left its imprint on Ratzinger, was a specifically Catholic one: the widespread global outrage at Paul VI's Humanae vitae, issued July 29, 1968. Many biographers of Paul believe that the anger generated by Humanae vitae, which reiterated the church's ban on birth control despite a widespread expectation that it would change, so shocked the pope that it explains why he never issued another encyclical during the final ten years of his reign. More than a thousand theologians from all over the world announced their dissent from the teaching, saying it contributed to "making war and poverty inevitable." They called it "immoral." Polls showed the overwhelming majority of Catholics felt the pope was "out of touch."

In Germany, some of the edge seemed to be taken off the reaction when the country's bishops, meeting in Königstein in August 1968, declared that couples who use contraception "must for themselves determine whether in conscience- free of subjective presumption-they can answer for their decision." If they felt they could do so, then use of birth control would not necessarily be a sin. The bishops noted the pope had not declared his teaching a dogma. The Austrian bishops put out a similar statement, called the Maria Troster declaration, as did more than twenty other bishops' conferences.

Yet at the September Katholikentag, a national Catholic gathering, in Essen, the controversy erupted anew. An Action Committee of Critical Catholics had come together to organize dissent from Humanae vitae. They expected a gesture of support from Cardinal Julius Döpfner, the liberal hero of Vatican II and the man who had chaired the pope's birth control commission, which recommended a change in teaching. At first Döpfner seemed prepared to offer support to the committee, but then he "switched," according to German theologian Uta Ranke-Heinemann, who was present at the event. "He started talking about how we must send a message of support to the pope, saying what courage he had shown and how correct he was. I was stunned." She said that Döpfner's attitude sealed the breach between many German Catholics and church authorities.

The events of 1968, former Ratzinger student Wolfgang Beinert told Time in 1993, "had an extraordinarily strong impact" on Ratzinger. He had been "very open, fundamentally ready to let in new things. But suddenly he saw these new ideas were connected to violence and a destruction of the order of what came before. He was simply no longer able to bear it."