This piece from The National Interest on the relationship between Hannah Arendt and Hans Morgenthau is compelling reading.
As a History undergraduate in the 1990s, I read a good deal of Hans Morgenthau's work, especially his classic Politics Among Nations (1948) and In Defense of the National Interest (1951). It was hard then (and still now) to imagine Morgenthau, the realist scold for cold war America, as a man inclined to matters of the heart, even if the need for love and companionship can afflict even the most hard-hearted among us. Despite reading all I could find as a student on not just Hans Morgenthau but Henry Kissinger and Walter Lippman, also, I was not previously aware of the Arendt-Morgenthau relationship and had not seen it mentioned in biographies, letters or recollections of those difficult times.
This TNI piece not only explores that but that Morgenthau's one-time love interest, if not muse, was, of all people, Hannah Arendt. They were people forged by the Depression, World War Two and the Holocaust, which, for some, was a cause for a deeper exploration of life's meaning while, for others, it was a lesson that life is transient and that the here and now may be all we have. These biographical details were lived experiences, often lived with fear and trepidation in Arendt's case as she sought to escape Nazi-occupied Europe, but which ensured that the haunting experiences of war, death and persecution informed both their work, and ensured it was never polluted by the cheap cynicism and snark of this time.