This was less than a decade after Bernstein had been called a fellow traveler by Life magazine, and just over a decade before Nixon recorded himself calling Bernstein a "son of a bitch." (Ironically, Life's accusation came on the heels of the infamous Cultural and Scientific Conference for World Peace, which probably indirectly led to the above encounter. The Conference, organized by the Soviet Union, prodded the CIA to focus attention and money on pro-American cultural diplomacy; the Institute of International Education award to Bernstein was largely based on such diplomacy, in the form of Bernstein's international tours with the Philharmonic.)
These kinds of archives tend to be fertile ground for reading between the lines, but one figure whose personality comes through largely unfiltered is my old teacher, Lukas Foss. A folder of documents surrounding Foss's guest conducting stints in the mid-1960s is chock-full of Foss's scattered, exuberant graciousness and Carlos Moseley's good-natured exasperation in trying to pin him down. There's also this glimpse of Foss's typically cheerful pragmatism, in this case regarding Bach's St. John Passion:
Regarding St. John Passion text, I feel very strongly that we should have no translation. Main reason: leaf rustling, but also important that we don't get all that dated anti-Semitism into print. Whenever it is done..., it produces a flurry of letters. Why not have a little harmless synopsis for each number, and on a single page or an adjoining page so there is no turn.