I have been trying to explain 1968 to 2008. It has not been easy – and not just because I was barely four years old in May 1968. Students today seem, to put it mildly, bemused by the 40th anniversary of les evenements de soixante-huit. “I was here in ’68,” enthused a parent who sat in on my lecture on the subject at Harvard a couple of weeks ago. “I remember the occupation of University Hall.” His daughter gave him the look my teenage daughter gives me when I try to explain the impact the Sex Pistols had on me when I was her age.

Harvard was not, of course, one of the epicentres of the higher-education earthquake of 1968, such as Berkeley, Columbia, Nanterre or Berlin’s Free University. But it was not without its seismic tremors. As at many universities, there was a branch of Students for a Democratic Society (SDS), and in 1968, having already organised successful demonstrations against campus visits by the secretary of defense, Robert McNamara, and a recruiter for the napalm manufacturer Dow Chemical, the group turned its fire against the Reserve Officers’ Training Corps, then an integral part of the university (ROTC instructors had the status of faculty members). The culmination came in April 1969, when members of the Worker-Student Alliance occupied the university’s main administrative building, evicted the deans working there and renamed it “Che Guevara Hall”.