Donald Trump issued a vague warning to former FBI Director James Comey last month:

“James Comey better hope that there are no ‘tapes’ of our conversations before he starts leaking to the press!” the president wrote on Twitter, three days after he unceremoniously fired Comey.

When I saw that tweet, I nodded in recognition. I worked for Trump for about three years in the late 1980s, as president and chief operating officer of the Trump Plaza Hotel and Casino in Atlantic City. I saw him regularly in meetings, phone calls, and updates of day-to-day operations.

After I resigned in April 1990, I wrote a book about my time with him, Trumped: The Inside Story of the Real Donald Trump, His Cunning Rise and Spectacular Fall, in 1991. In the book, I told stories about Trump’s leadership style that would come to echo his presidency years later.

I witnessed him make public phone calls that he insisted were private and use those conversations to humiliate and corner the person on the other end. I witnessed him demand loyalty from those who worked for him. I witnessed him make impulsive decisions as a result of his short attention span.

So when news of the Comey firing broke last month, as well as Trump’s subsequent warning to Comey that he might have recorded conversations with him, Trump’s behavior struck me as all too familiar. He was displaying characteristics I’ve been telling people about for decades.

Trump has a history of making private conversations public

Soon after I started working for Trump, I was told to never assume that a call from Donald was private. He liked to make phone calls while he had visitors in his office, leading the person on the other end to believe they were having a private conversation. This has been backed up by reports from ex-employees that recording calls or secretly revealing private phone calls is a common Trump tactic.

Once during a call from Trump, he casually asked me what I thought about a reporter from Atlantic City, a journalist who put out a monthly industry newsletter. I had no idea where he was coming from with the question, so I told him the truth — that I did not trust the guy and that I was cautious when I spoke to him.

The next day, that same journalist came barging into my office, demanding to know why I’d badmouthed him to Trump. He said that he was trying to get Trump to hire him as a consultant, and I might have ruined his chances to be hired by him. He then told me he was sitting with Trump during the call. Ouch.

It was also not beneath Trump to call a lower-level employee and ask them what they thought of a fellow executive in the company, unaware that that person was sitting in his office right there and then.

Trump has always enjoyed threatening people; he likes to keep people wondering what might be true or not true. Even if I suspect he didn’t actually record his conversations with Comey, Trump probably suggested he did to try to keep Comey off balance.

Loyalty is the most important thing to Trump — and if you don’t demonstrate that, you’re out

The decision to fire Comey in the first place was also classic Trump. Trump inherited Director Comey. He did not hire him for the job — President Barack Obama did. Trump is highly suspicious of everyone who works for him. It takes years to gain trust, and full trust probably only happens with family members. I doubt he is 100 percent confident in anyone other than his children.

He demands loyalty from all working for him, even if it is forced loyalty. While I worked for Trump, he would constantly seek reassurance from myself and other executive staff that we were behind him 100 percent. Often he would say things like, “I’m the best guy to work for, right? You’re never going to leave me, right?”

He also demanded that all employees sign letters of nondisclosure, prohibiting them from speaking about their time working in the organization. This is forced loyalty; if one is prohibited from speaking about Trump, they cannot refute his words. After I left the organization, it is my understanding that the nondisclosure policy was enforced throughout all of his businesses.

Trump hates it when people don’t agree with him, but particularly when they refute something he has said. Comey did this several times. The common theory at the moment is that Trump fired Comey because of the FBI's investigation into Russia's involvement with the 2016 election. And that theory is compelling, especially in light of the revelation that Trump asked Comey to drop his investigation into Michael Flynn over his contacts with the Russian government. However, I think the roots of the firing are elsewhere: in Comey's decision to contradict the president on whether the Obama administration wiretapped Trump Tower. Once that happened, it was over for him.

When I resigned from the job, Trump immediately said that he had fired me. In his mind, if one of his employees resigns, it looks bad. But if he can say that he fired the employee, he wins.

He continued to attack me after I left, particularly after word was out that I was writing a memoir. He made several statements to newspapers after the book was announced. One of his more famous quotes about me is in an interview he did with Playboy Magazine. When asked about the book, he said, “the stuff O'Donnell wrote about me is probably true. He is a fucking loser, a fucking loser,” which makes me laugh every time I think about it. I suddenly became a “loser,” a disgruntled former employee, a terrible manager, and a poor leader.

He also said that he hardly knew me and that he had spoken to me only a few times. He was so blinded with the need to put me down that he didn’t realize just how silly it sounded for him to make such a claim when I worked for him for three years. His spin of self-preservation was all that mattered.

The manner in which Trump chose to fire Comey — a letter delivered by a member of his security team when Comey was out of office — also came as no surprise to me. Despite Trump’s reputation for using the words, “You’re fired,” he has rarely used them in real life. Most true leaders have the decency and backbone to sit down face to face with key staff when the time comes to let them go. But Trump has always been the kind of leader that uses others to do his dirty work.

The Trump Taj Mahal opening was one of the best examples this. He would be talking with a particular employee who was involved in the disastrous opening, and after the person would leave the room, he would say, “Fire him, and if I see him around, I will fire you too.” He also did this with vendors all the time too. He would agree to a price for some service, then direct us to backtrack and refuse to pay unless they lowered the price.

Trump does explode at times in meetings, and he can say some very aggressive and nasty things to people. But he does not confront the issue on an intellectual basis, actually being constructive while ranting. He is simply an abusive communicator, calling names and degrading people.

I worked several years for another legendary figure in gaming, Steve Wynn. He too had a temper, and was prone to rant when he was not happy about something. But the key difference in Wynn’s rants was that he would actually be teaching you something. I learned from Wynn every time I spoke to him. That was not true of Trump. With him, I came away from every conversation feeling confused and bullied.

Trump has a short attention span and makes impulsive decisions

I believe Trump had been considering Comey’s future at the FBI for some time — he said it himself! But that is true for just about anyone working under him. Everyone is susceptible to constant evaluation. He can love you one day and hate you the next.

Still, the suddenness of the firing caught people off guard. But it shouldn’t have — as I reported years ago, Trump has a very short attention span. This also translates to him not being able to think through the entire decision-making process. Trump is just not capable of thinking something to conclusion. His thought process is so limited, so “in the moment,” that he does not see consequences for decisions he wants to make right now. He just does it.

That short attention span is something employees had to get used to quickly. When we would need him to review new television ads or concepts, we would have to very strategically figure when to make presentations to Trump. First we would have to make sure he was in a good mood. If he was in a bad mood, he would like nothing. If he was in good mood, we would have the presentation down to literally less than five minutes. If it were any longer, he would begin to fidget or just get up and leave the meeting. We would then have to wait for another occasion to represent the concept, which could be days or weeks.

In the wake of the Comey firing, politicians and pundits continue to react with confusion at the impetus behind Trump’s actions. His follow-up tweet threatening to release “tapes” on Comey added more fuel to the fire. “I've spent the last several hours trying to find an acceptable rationale for the timing of Comey's firing. I just can't do it,” said Sen. Jeff Flake of Arizona.

I’ll never know for sure what’s behind Trump’s actions. But based on my experience working for him, this behavior is not surprising. It’s completely within character for Trump to demand utter loyalty from those with whom he surrounds himself — the concept of a “subordinate” as a check on his power is foreign to him. His insecurity feeds this desire to do all he can to remain the most powerful guy in the room.

This is the man we elected. In Trump’s world, if you hire someone, you have power over him or her. He believes, above all, in power over individuals.

Jack O’Donnell is businessman who consults with companies and private equity firms involved in hospitality, gaming, and behavioral health. He was the president and chief operating officer at Trump Plaza Hotel and Casino, working directly for Donald Trump, during its most successful years. He wrote a book about Trump called Trumped: The Inside Story of the Real Donald Trump, His Cunning Rise and Spectacular Fall.

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