I learned a great deal about rentier economies, as they’re sometimes known, when I spent a year in Baghdad, covering the American occupation of Iraq between 2003 and 2004. I met many of Iraq’s leading businesspeople, and they always talked about ‘‘deals.’’ As one explained to me, there would be some business opportunity — building a hospital, say, or getting a license to import a new line of cars — and Saddam Hussein’s family would essentially auction off the opportunity to the handful of wealthy businesspeople whom they deemed trustworthy. Success came not from being better at building hospitals or more efficient at importing cars. It came from understanding the internal family politics of the Husseins and the power of the state bureaucracy.

As an economic journalist, when trying to explain the idea of rent-seeking, I have always used one quintessential example from the United States — a sector in which markets don’t function, in which excess profits are held by a few. That world is Manhattan real estate development. Twenty-three square miles in area, Manhattan contains roughly 854,000 housing units. But there are many more people than that who want to own property there. A Manhattan pied-à-terre has long been a globally recognized sign of wealth and status — especially in recent years, as billionaires the world over have come to see a Manhattan condo, even one rarely visited, as a vessel for laundered wealth or a hedge against political upheaval at home.

Manhattan real estate development is about as far as it is possible to get, within the United States, from that Econ 101 notion of mutually beneficial transactions. This is not a marketplace characterized by competition and dynamism; instead, Manhattan real estate looks an awful lot more like a Middle Eastern rentier economy. It is a hereditary system. We talk about families, not entrepreneurs. A handful of families have dominated the city’s real estate development for decades: Speyer, Tishman, Durst, Fisher, Malkin, Milstein, Resnick, LeFrak, Rose, Zeckendorf. Having grown up in Manhattan myself, I think of these names the way I heard Middle Easterners speak of the great sheikhs who ran big families in Jordan, Iraq and Syria. These are people of immense power and influence, but their actual skills and abilities are opaque. They do, however, make ‘‘deals.’’

In recent weeks, hearing Trump talk, I’ve realized that his economic worldview is entirely coherent. It makes sense. He is not just a rent-seeker himself; his whole worldview is based on a rent-seeking vision of the economy, in which there’s a fixed amount of wealth that can only be redistributed, never grow. It is a world­view that makes perfect sense for the son of a New York real estate tycoon who grew up to be one, too. Everything he has gotten — as he proudly brags — came from cutting deals. Accepting the notion of a zero-sum world, he set out to grab more than his share. And his policies would push the American economy to conform with that worldview.

Many economists and political scientists now think that the United States economy has shifted, over the past few decades, toward one in which a higher proportion of the economy comes from so-called rents: Wall Street’s maneuvering through the regulatory process, ‘‘free-trade’’ deals whose thousands of pages of rules wind up prescribing winners and losers. The left, right and center of the economics profession all agree that reducing rent-seeking behavior, and improving overall growth, is essential if we want to ‘‘make America great again.’’