On 12 January 1969, Herbert Marcuse wrote to Theodor Adorno announcing a June visit to Frankfurt. He wanted to give a lecture. He requested that the meeting be small and intimate, and solicited an official invitation, so that he could get leave from the University of California. This was to be the beginning of a summer in Europe, lecturing in Italy, and all-importantly, swimming. That there were tensions between the two old acquaintances was evident from Adorno’s hand-written comments on the letter. He suspected that the need for water, and hence the need to avoid Adorno’s holiday home in Zermatt, was an excuse masking Inge Marcuse’s concern that the Frankfurt theorists would be a bad influence on her husband. Adorno eagerly noted ‘At least he is starting to notice it!’ in the margin when Marcuse conceded that irrational tendencies plagued the student movement and that, because of the issues raised by black politics, the American situation was more complicated and dangerous.footnote¹ An additional scribbling on the letter, for Horkheimer’s eyes, echoed the idea that there should be no great fuss and ‘official circus’ around Marcuse’s Frankfurt speech. Exposing his nervousness about the Institute providing a platform for the celebrated supporter of the revolutionary student movement, Adorno toyed with the idea of withdrawing the invitation.footnote²

Marcuse, heralded in the blurb for the mass-circulation paperback One Dimensional Man as the prophet of the student revolutionary movement ‘along with Mao Tse Tung, Che Guevara and Ho Chi Minh’, would be arriving in a volatile Frankfurt scene. Demonstrations and occupations of university buildings were a regular occurrence. Leaflets and pamphlets were issued daily. Seminars turned into political meetings and student strike committees demanded the self-organization of studies or co-control; a grouping called the ‘Spartakus department’ planned alternative courses on left radicalism, revolutionary theory—from Rosa Luxemburg to the use of cobblestones—critical economics, authority and communication, and work prospects. Students versed in critical theory were demanding that theoretical critique turn into practical political action. Theory was a brake on the movement, alleged some, as they denounced fellow students—mocked as Adornites and Habermice—for promoting theory for theory’s sake and disregarding their professors’ function as a left alibi for bourgeois society.footnote³ The Frankfurt Schülers, ‘left idiots of the authoritarian state’, had become ‘critical in theory, conformist in practice’, stated a leaflet put out by sociology students in December, and it quoted Horkheimer’s Dämmerung from 1934: ‘A revolutionary career does not lead to banquets and honorary titles, interesting research and professorial wages. It leads to misery, disgrace, ingratitude, prison and into the unknown, illuminated by only an almost superhuman belief’.footnote⁴ In March 1969, a pirate edition of Dämmerung appeared, and on its back cover was a photograph of the sociology department under occupation, renamed Spartakus department and festooned with a banner that quoted words from the book: ‘If socialism appears unrealizable then it is necessary to make it a reality with an even more desperate determination.’footnote⁵ Discussions were heated in Frankfurt. Some activists had been going further, grasping at alarmist tactics. In April 1968, Andreas Baader, Thorwald Proll, Horst Söhnlein und Gudrun Ensslin set two Frankfurt department stores alight, ‘as a protest against the indifference to war in Vietnam’.footnote⁶ At the end of October 1968 they were sentenced to three years imprisonment each.

The tensions between the professors at the Institute for Social Research and student activists had been building since May 1964, when Adorno instituted legal proceedings against some pranksters, members of the situationist-inspired group Subversive Aktion. They had pinned up ‘Wanted’ notices in university areas, comprised of a montage of Adorno quotes—‘There can be no covenant with this world; we belong to it only to the extent that we rebel against it’, ‘All are unfree under the illusion of being free’, ‘Theft of free time is presented as organized amusement’, and so on—and the notice concluded that all those who agreed that the discrepancy between analysis and action is unbearable, should contact Th. W. Adorno, 6 Frankfurt am Main, Kettenhofweg 123, citing the reference ‘Antithesis’.footnote⁷ Adorno was incensed by the unauthorized use of his name. Two men were prosecuted and fined for offences against the press law, after Ernst Bloch had persuaded one of his students to name those responsible. But the poster had other effects. In West Berlin the call was answered by two East German students, Bernd Rabehl and Rudi Dutschke. Dutschke was to become the theoretician of student activism in West Berlin, while his counterpart in Frankfurt was Hans-Jürgen Krahl, one of Adorno’s doctoral students. In September 1967, at a German Socialist Student Alliance [Sozialistischer Deutscher Studentenbund, sds] conference in Frankfurt, a keynote paper on organization by Dutschke and Krahl asserted to need to act as ‘urban guerilleros’. The university, they said, could act as the urban guerrilla’s shelter, from where he could organize the struggle against institutions and state power. The university was to be the garrison of the Extra-Parliamentary Opposition [Außerparlamentarische Opposition, ApO].

A series of protests, involving the boycott of lessons, had been underway since early December 1968. Activists in the sds were challenging an attempt to reduce the period of study and other university reforms. Sociology students, mainly sds, formed the core of the protests. On 31 January 1969, Krahl and a group of students headed for the sociology department, intending to occupy. Finding it locked, the students transferred to the Institute for Social Research to co-ordinate their strike activities. Adorno and Friedeburg called the police and 76 students were arrested. As Krahl was forced through a cordon of police, he screamed at Adorno and Friedeburg ‘Scheißkritische Theoretiker’. He was the only occupier not released that evening. That event and its repercussions dominate the letters that Marcuse and Adorno exchanged over the next eight months.

The next day, some of the students ran amok in Café Kranzler, demanding Krahl’s release. Adorno did not have to resort to street tactics to put his points across. There were countless interviews on why critical theory did not lead directly to political practice, and the radio stations broadcast his lectures, such as ‘Resignation’ and ‘Critique of Positivism’, while Stern illustrated a photograph of the University rector raising a chair to defend himself against students with a quote from Adorno: ‘I proposed a theoretical model for thought. How could I suspect that people would want to realize it with Molotov-cocktails?’. Marcuse, for his part, was more inclined to give interviews with headlines such as ‘Student Protest is Non-Violent Next to the Society Itself’.

On 25 March 1969, Adorno informed Marcuse that the charges against seventy-five of the occupiers had been dropped. Only Krahl was to face trial. Adorno reported intense pressure to drop the charges, and, while Habermas felt inclined to do so, Adorno and Friedeburg, though still undecided, thought that they would not. Adorno admitted that he dreaded the recommencement of his teaching duties ‘given some people reckon with bombs and shoot-outs’.footnote⁸ Propaganda and attacks on the Institute and its members continued. On 22 April 1969, Adorno had just begun his lecture ‘Introduction to Dialectical Thought’ when a student interrupted him from the back of the auditorium, and another wrote a rhyme on the blackboard: ‘Wer nur den lieben Adorno läßt walten, der wird den Kapitalismus sein Leben lang bewalten’ [Whoever gives dear Adorno control will preserve capitalism for the rest of his life]. Then three female students in leather jackets came forward, tossed tulips and roses at Adorno, exposed their breasts to him and tried to kiss his cheek. The seats were strewn with flyers declaring ‘Adorno as institution is dead’.footnote⁹ The stunt split the student movement, for there were people who thought that, rather than disrupt lectures completely, they should be turned into venues for political discussion. The leather-jacket fraction of the sds was indulging in action for action’s sake. Anyway, Adorno had had enough, and cancelled his lecture series.

On 23 May 1969, Marcuse decided that he could not go to Frankfurt. He apologized to Adorno for not managing to reply till then to his letter from 5 May, because of events in California. Governor Ronald Reagan had attempted to clear occupying students from the People’s Park using heavily armed police with bird shot, buck shot and rock salt, while helicopters released tear gas. One hundred and twenty-eight people were wounded. The National Guard was deployed and a curfew announced. The death of a student brought masses out for a vigil. This, too, was attacked from the air. After further repression, the Californian universities, including Marcuse’s San Diego campus, began a strike on 26 May. Marcuse, however, had not stayed. He was in Europe, and about to be drawn into his own controversy. On 2 June, the magazine Konkret celebrated Marcuse as ‘the only representative of the “Frankfurt School” who supports those who wish to realize the claims of Critical Theory: the students, young workers, persecuted minorities in the metropolises, and the oppressed in the Third World’.footnote¹⁰ Two days later, a left-wing Berlin newspaper claimed that Marcuse had worked for the us Secret Service until the 1950s and possibly into the 1960s.footnote¹¹ The story stemmed from the historian L.L. Matthias. Conspiracy theories started to emerge, and the revelation led to disruption of Marcuse’s lecture tour in Italy. On 17 June, Daniel Cohn-Bendit interrupted the Rome lecture in the Teatro Eliseo with some questions: ‘Marcuse, why have you come to the theatre of the bourgeoisie? Herbert, tell us why the cia pays you?’. Newspapers reported that Marcuse had to leave the theatre.footnote¹²