After Donald Trump's stunning victory two weeks ago, one of Gautam Mukunda's friends posted to his Facebook page, asking if he had a time machine. Back in 2012, Mukunda, an assistant professor at Harvard Business School who studies political leadership, published a book that examined the career patterns and performance of American presidents. Its first chapter reads like something out of this year's election. "When someone manages to bypass the process that filters candidates for office, a leader who is very different from all the people who almost won can gain power," Mukunda wrote in "Indispensable: When Leaders Really Matter." "If that leader is sufficiently unconstrained, he or she can have a large impact."

Mukunda's research compared historians' rankings of this nation's best and worst chief executives with how much experience they had in national political office. Those who have a lot of it he calls "filtered." Those without much time in national positions, or who had it but came to power over the opposition of elite insiders, he calls "unfiltered." What he found: The relative outsiders, or "unfiltered" presidents, tended to fall among both the very best and the very worst chief executives in the historians' rankings. Those with more long-term, insider political careers were more likely to fall in the middle of the pack. And in Mukunda's terminology, Trump is as unfiltered as they come.

Yet despite studying the history of relative outsiders who have been president, Mukunda, a Democrat, recently wrote an op-ed in the Harvard Business Review about how certain he had felt about a Hillary Clinton win. We spoke with Mukunda about his research, what it could tell us about a Trump presidency and what advice he might have for the president-elect. The conversation below has been edited for length and clarity.

In your book, you talk about how research has traditionally told us that individual leaders don't really make that much impact. Can you explain?

Most social science research on leaders says that leaders matter very little, if at all. It says that basically most leaders were roughly the same as the people who might alternately have had the job. What that new person would do is no different or not significantly different from what the original person would do. And so the outcome of that is the identity of individual leaders doesn’t matter that much. What really matters is the system which selects them and the pressures and constraints they face once they’re in power.

How much more freedom is there for outside leaders to crop up in a democracy, in the American democracy, compared to other institutions?

It depends on the democracy. Parliamentary democracies -- they have almost no freedom for outsiders to come in. The United States, pretty much uniquely for major countries, has an exceptional degree of freedom for outsiders to come in. When I wrote my book [in 2012], I didn’t include President Obama in my set, but I said that half the presidents of the United States I would classify as "unfiltered leaders." It's not the same thing as outsiders, but it's similar.

So define the term for us.

An unfiltered leader is basically a leader who fits into one of two categories. In one, the elites who play a major role in choosing who the leaders are -- the people who control the parties, senior members of the government -- either they know very little about the person, so they have little ability to predict what this person will do in office. Or, based on what they know about the person, they are opposed to that person gaining power but somehow they get it anyway.

But even the presidents who are unfiltered leaders, in your view, had still at least held political office of some kind. Compare them with Donald Trump, and it almost seems like you would need a new category.

It's as if he stepped out of the pages of my book as the most extreme possible example of my theory. It is impossible to be less filtered than Donald Trump. We have pegged the scale. Unless we pick someone random off the street, we've managed it. We’ve never before elected a president of the United States who had no experience in government or the military.

Who were some of the best unfiltered presidents?

Abraham Lincoln’s only national political experience was one term in the House of Representatives. He was an extreme dark horse candidate for the Republican nomination. Basically no one expected him to get it because he was a relatively minor figure.

He was such a success because he did things that, if people had known he was going to do those things, they would never have voted for him. That knowledge link is key. Lincoln positioned himself in the campaign as the least anti-slavery Republican -- the Republican most likely to conciliate the South. And then when he went into office, of course, he wasn’t that at all.

And among the bottom?

The classic example is Warren Harding, the guy who was so totally unqualified for the presidency that he acknowledged it himself. In Malcolm Gladwell’s book ["Blink"] he talks about the "Warren Harding error." Harding became president because he looked like a guy Hollywood would cast as the president of the United States. He wasn’t terribly bright, and the people around him were incredibly corrupt. He wasn’t really interested in the job. He used to like to play poker in the Oval Office with people in his team as opposed to actually being president.

In your book, you write that outside leaders, because they tend to make choices no one else would make, "may succeed brilliantly or fail catastrophically. They are unlikely to be mediocre." What does history say about outside leaders and their chances at success or failure?

I do not expect [Trump] to follow through on many of his campaign promises because one of the hallmarks of unfiltered leaders is that precisely because they don't have a record, they can promise anything in order to get to power. They have more freedom to deviate because those promises have no reflection of their underlying beliefs. That can work out to their benefit. But that being said, the people who are thinking that "gee, this is normal" are deluding themselves.

There's this idea that being in office, people will be moderated by power, or moderated by forces that constrain them. Institutionally, Donald Trump is less constrained than almost any president in modern American history. Like Barack Obama, he’s coming in with a majority in both the House and the Senate. Unlike Obama, he will also have the ability to [shift] the majority on the Supreme Court. And the Republican party is vastly more disciplined in terms of the level of party discipline than the Democratic party.

Now, focusing on what we can learn from my theory: What it demonstrates is the idea that people will be moderated by being in power is almost always false. When you are trying to gain power you say things meant to please the people who will decide whether or not you’re going to get power. That’s your goal. You want to please them in order to gain office and gain power. Once you’re in office, that's what you have. You have power. Power is not a moderating force. Power is a liberating force.

So what does your research say about the chances for Trump to have a mediocre term? 

It's pretty low. That’s not how historians will assess him. It’s possible but highly unlikely. ... A highly successful Trump presidency is possible. My theory says you should not discard that possibility. That being said, if you were to pick an unfiltered person to be the president of the United States, it would be hard to imagine someone with worse odds of being a success than Donald Trump. 

You write about charismatic leaders, particularly narcissistic ones, and their ability to, again, either be extreme successes or failures. You call charisma an "intensifier." What does that mean?

Intensifiers basically make good things better and bad things worse. Charisma is a classic example. I define charisma as the ability to persuade people to do things through force of personality that you cannot persuade them to do [otherwise]. If the ideas you are trying to persuade them to are good ones, then charisma is incredibly valuable. If they are bad ones, than charisma is incredibly dangerous.

Clearly a very large proportion of the American population is affected powerfully by [Trump's] charisma. He himself said this his followers are so committed that he could shoot someone on Fifth Avenue and they would still vote for him. That’s a pretty remarkable charismatic hold: That’s almost classically the definition of a charismatic leader who gets extraordinary amounts of adulation from their followers. You should expect that level of charisma to enable him to do things that a normal political leader simply could not even contemplate.

What advice would you have for an unfiltered president?

The advice I would give for any unfiltered leader is: You made it because you are unfiltered, and that doesn’t mean that you should act normal. You are who you are and you were chosen for who you are. But it does mean that you should appreciate that there are reasons that people acted the way they did in the past, and that running an organization is invariably vastly more difficult than criticizing the running of an organization. You will find that being a leader is much much harder than telling people how much better a job you would do if you were the leader. So you should take the advice of people who are experienced and the counsel and the help of people who have been there before. You should take it incredibly seriously.

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