'This irony recurs in his letters: Le Carré repeatedly offers withering indictments of the powers he served, but he never seems to cast them aside. Later in life, he wrote nostalgically to Alan Judd, a fellow novelist who once served as a soldier and diplomat, of his time at MI5 and MI6: “I miss the Office … In a sense, they are the only places, apart from writing.”
https://www.theatlantic.com/books/archive/2023/02/john-le-carre-spy-came-in-from-cold-book/673227/