In August, 2016, Cliff Sims, the C.E.O. of an Alabama-based conservative news site, joined the Trump campaign. He then followed Trump to the White House, where he worked as the special assistant to the President and as the director of White House message strategy, before resigning last year. On Tuesday, Sims published a book that is already a best-seller, called “Team of Vipers: My 500 Extraordinary Days in the Trump White House.” It’s a gossipy tell-all, sprinkled with stories of Trump yelling at Paul Ryan, Sims battling John Kelly, and a West Wing full of unseemly people looking out for their own interests. Predictably, after the White House declined to comment on the book, Trump himself lashed out at Sims over Twitter on Tuesday morning, writing, “A low level staffer that I hardly knew named Cliff Sims wrote yet another boring book based on made up stories and fiction. He pretended to be an insider when in fact he was nothing more than a gofer. He signed a non-disclosure agreement. He is a mess!” (The chief operating officer of the Trump campaign tweeted that the campaign will file a lawsuit against Sims.)

In fact, the President comes across better in the book than most of the people around him do—and better than he has in most of the other books written about this White House. Sims has doubts about Trump’s management style and occasionally about his rhetoric, but he remains fundamentally a believer. I spoke with Sims on the phone on Tuesday afternoon. During our conversation, which has been edited and condensed for clarity, we discussed whether Trump is responsible for the people around him, how Sims views Trump’s approach to governance, and why he refuses to believe that the President might be a racist.

Are you proud to have served in the Trump Administration?

Yeah, it’s one of the last things I say in the book. I am proud to have worked for the American people, proud to have worked in the White House. And proud to have worked in the Donald Trump White House, in spite of a lot of the misgivings that I had—and I lay them all out in the book. It is an opportunity of a lifetime, and I am glad I did it.

By misgivings, do you mean serving this President specifically, or do you mean the people surrounding him?

Yeah, so, man, there is a lot to unpack there. There are certainly things that the President has done or said that I disagreed with at various times. And some of the things even prior to him being in the White House, things in the campaign obviously would make any Southern Christian boy from Alabama a little squeamish at times. And then the people around him—I think I am pretty clear in the title, “Team of Vipers,” that it is a tough place to work. But, you know, I include myself in the team of vipers, and certainly there were things I did there that I wish I had done differently at various times.

What was the biggest flaw of the people who surrounded Trump?

I think there is an inherent selfishness that is deeply ingrained in some corners of that building. There are various times in the book where I point out my own selfishness—maneuvering to push this staffer out, or to undermine this other colleague, or whatever it might be—and I justified those by saying it would be better for the President if this person were not doing this, that, or the other, but in reality, in retrospect, it was better for me. Those were selfish moves by me. And I think a lot of what I saw in there came from a very selfish place, and one of the criticisms I have of myself is that I didn’t have a servant’s heart a lot of the time while I was there. And that’s a criticism I would apply to a lot of people there.

Do you think there is something about the President that attracts people with these traits, or do you think this is true in every Administration?

I am not sure.

You are not sure?

It is the only White House I have ever worked in. I would have to imagine that any White House is going to be a very competitive environment, attract certain types of people who are clawing for those types of jobs. I bet a lot of it is not abnormal. I do think that the atmosphere that was created there—the work culture—bred that, exacerbated that. And, in any workplace, the culture is driven from the top down. And so I think there probably is something about the way the President leads his team that results in that kind of atmosphere. What exactly that is, I am not sure.

We can all agree that the President is not the most honest person on earth, and many people close to him have been indicted for lying to investigators. You have a President who has not completely separated himself from his business, and you have a lot of people close to him who seem like they are out to make a buck. Do you think there is a connection?

I don’t know. I have never really considered it in that context, man.

You have never considered it?

No, not in that way, exactly. I would like to give that thought a little more consideration before giving a response to it.

Consider it now. You know the President is not always honest with words, and many of his associates have gotten into trouble for lying to investigators. I am curious where you think that culture comes from.

I kind of think I just answered that question. Every culture starts from the top down. I think that you are hitting on something there, and I get where you are coming from, I just don’t know how to articulate how I feel. I think you have a point, but I am not sure how to add to it.

In the book, you write, “The Charlottesville response did not cause me to reconsider working in the White House, the way it seemed to with others. Part of it may have been that I was battle-hardened after a year in the foxhole. But I also just flat-out did not think he was racist. . . . I personally never witnessed a single thing behind closed doors that gave me any reason to believe Trump was consciously, overtly racist. If I had, I could not have possibly worked for him.” Do you want to expand upon that?

Yeah, yeah. I think there is another scene in the book that is illustrative of— Well, so, like, the Congressional Black Caucus meeting in the book, where they came in kind of loaded for bear and ready to really give it to him, and then they sit down with him and realize the same thing a lot of people do, which is: Man, you kinda just can’t help like the guy when you get in the room with him. He is very gregarious and a great host. I really don’t think there is a racist bone in his body. I can keep going on this, though, because I have thought a lot about this.