To be sure, one’s colleagues might well be wrong, but they are usually operating in good faith, and they are owed a duty of loyalty. And while Gates appears to have a phenomenal memory, it would be astounding if everything happened in exactly the way he says it did.
Of course, the duty of loyalty isn’t absolute. If an administration has engaged in serious wrongdoing, that duty can be overcome. Undoubtedly, the duty recedes over time. There is a plausible argument that high-level advisers have more room to disclose confidential communications after the president whom they served leaves office.
Maybe Gates meant to write for history; maybe he thought that by offering an insider’s view of what happened, he was doing a service for posterity. But most of his disclosures add nothing of importance to the historical record. He could easily have written a different book, drawing on his extraordinary and admirable public service and exploring past and present issues, without revealing private discussions.
Gates is an honorable man. He was an honorable public servant. But in breaching the trust of his former colleagues, he has committed a dishonorable act.