But perhaps Powell seems so reasonable precisely because he is so in sync with today’s conventional wisdom. It would be absurd for him to run for president, he writes to a fan (former Obama Veterans Affairs secretary Eric Shinseki), because the most important to-do list involves things outside of presidential authority: “Toss out Congress incumbents that do nothing, fix taxes, fix the infrastructure, get super rich money out of the system, eliminate Gerrymandering, etc.” Donald Trump, he writes to a former aide, “has captured the frustration and disappointment of average folks and not just racist nuts” but is “not the solution to their problems and angst.” The G.O.P. primaries had become “a reality show with Trump playing the role of Jerry Springer.”

You would be hard-pressed to throw a stone in Washington or Manhattan and hit anyone who disagreed with these things. And Powell seems obviously correct: campaign financing is a big problem; congressional gridlock is a problem; tax law is too messy; congressional districting is done sleazily. As for Trump, yes, it’s unlikely that he’ll fix people’s problems.

But it’s striking how few challenges Powell is likely to experience to these beliefs. Even as Democrats have accused Republicans of “epistemic closure” in their beliefs, the bipartisan governing class may have similar problems of its own. Powell’s emails make clear that he lives a life of television appearances, lucrative paid speeches, and expensive parties at which he runs into a bipartisan assortment of colleagues. Recalling his frustration over being dragged into email controversy by Clinton’s staff, Powell writes, “I had to throw a mini tantrum at a Hamptons party to get their attention.”