Historian Kyle Harper joins the show to discuss his book The Fate of Rome: Climate, Disease, and the End of an Empire. We discuss the fall of the Roman empire and the new scientific discoveries that have shed more light on its nature and causes. Kyle’s work looks at the epidemics and climatic changes that hit the empire, contributing to its disintegration.
Interweaving a grand historical narrative with cutting-edge climate science and genetic discoveries, Kyle Harper traces how the fate of Rome was decided not just by emperors, soldiers, and barbarians but also by volcanic eruptions, solar cycles, climate instability, and devastating viruses and bacteria. He takes readers from Rome’s pinnacle in the second century, when the empire seemed an invincible superpower, to its unraveling by the seventh century, when Rome was politically fragmented and materially depleted. Harper describes how the Romans were resilient in the face of enormous environmental stress, until the besieged empire could no longer withstand the combined challenges of a “little ice age” and recurrent outbreaks of bubonic plague.
Our discussion addresses some common concerns about housing markets. For instance, why do new luxury homes sometimes sit empty? What’s the deal with Houston’s land-use laws? And what can we do about the urban housing crisis?
Psychologists have long understood that social environments profoundly shape our behavior, sometimes for the better, often for the worse. But social influence is a two-way street—our environments are themselves products of our behavior. Under the Influence explains how to unlock the latent power of social context. It reveals how our environments encourage smoking, bullying, tax cheating, sexual predation, problem drinking, and wasteful energy use. We are building bigger houses, driving heavier cars, and engaging in a host of other activities that threaten the planet—mainly because that’s what friends and neighbors do.
In the wake of the hottest years on record, only robust measures to curb greenhouse gases promise relief from more frequent and intense storms, droughts, flooding, wildfires, and famines. Robert Frank describes how the strongest predictor of our willingness to support climate-friendly policies, install solar panels, or buy an electric car is the number of people we know who have already done so. In the face of stakes that could not be higher, the book explains how we could redirect trillions of dollars annually in support of carbon-free energy sources, all without requiring painful sacrifices from anyone.
Most of us would agree that we need to take responsibility for our own choices, but with more supportive social environments, each of us is more likely to make choices that benefit everyone. Under the Influence shows how.
During the 2016 presidential election, both Donald Trump and Bernie Sanders argued that elites were hurting the economy. But, drawing together evidence and theory from across economics, political science, and even finance, Garett Jones says otherwise. In 10% Less Democracy, he makes the case that the richest, most democratic nations would be better off if they slightly reduced accountability to the voting public, turning up the dial on elite influence.
To do this, Jones builds on three foundational lines of evidence in areas where he has personal experience. First, as a former staffer in the U.S. Senate, he saw how senators voted differently as elections grew closer. Second, as a macroeconomist, Jones knows the merits of “independent” central banks, which sit apart from the political process and are controlled by powerful insiders. The consensus of the field is that this detached, technocratic approach has worked far better than more political and democratic banking systems. Third, his previous research on the effects of cognitive skills on political, social, and economic systems revealed many ways in which well-informed voters improve government.
Discerning repeated patterns, Jones draws out practical suggestions for fine-tuning, focusing on the length of political terms, the independence of government agencies, the weight that voting systems give to the more-educated, and the value of listening more closely to a group of farsighted stakeholders with real skin in the game—a nation’s sovereign bondholders. Accessible to political news junkies while firmly rooted and rigorous, 10% Less Democracy will fuel the national conversation about what optimal government looks like.
What is it like to sit in the Oval Office and discuss policy with the president? To know that the decisions made will affect hundreds of millions of people? To know that the wrong advice could be calamitous? When the President Calls presents interviews with thirty-five economic policymakers who served presidents from Nixon to Trump. These officials worked in the executive branch in a variety of capacities—the Council of Economic Advisers, the Office of Management and Budget, the Department of the Treasury, and the National Economic Council—but all had direct access to the policymaking process and can offer insights about the difficult tradeoffs made on economic policy. The interviews shed new light, for example, on the thinking behind the Reagan tax cuts, the economic factors that cost George H. W. Bush a second term, the constraints facing policymakers during the financial crisis of 2008, the differences in work styles between Bill Clinton and Barack Obama, and the Trump administration’s early budget process.
When the President Calls offers a unique, behind-the-scenes perspective on US economic policymaking, with specific and personal detail—the turmoil, the personality clashes, the enormous pressure of trying to do the right thing while the clock is ticking.
Critics argue that maritime policy is protectionist legislation that restricts competition and reduces economic efficiency. In this paper, I argue the contrary. I begin with the premise that the primary role of the state is to provide national defense. A country must be able to protect its wealth, and therefore its capital, from plunder and/or destruction. This implies that a sufficient level of defense spending is increasing in the capital stock. An efficient solution is to tax capital to finance defense. Nonetheless, there is reason to believe that capital devoted to shipping imposes a lower marginal defense cost than other forms of capital because ships can be used as a naval auxiliary. If so, then one would expect that the optimal tax rate on shipbuilding and the merchant marine would be lower than other capital-intensive firms. Put differently, maritime subsidies during peacetime can be understood as the result of a Coaseian bargain in which the government compensates shipbuilders and the merchant marine during peacetime in exchange for their services during wartime. I argue that the history of U.S. maritime policy is broadly consistent with my theory. I conclude by discussing the current state of the merchant marine and maritime policy.
Today’s episode features Gilles Duranton and Diego Puga on their new working paper, “Urban Growth and its Aggregate Implications.” This paper builds a detailed theoretical model that includes urbanization, agglomeration economies, inter-city migration, congestion externalities, and land-use restrictions.
We develop an urban growth model where human capital spillovers foster entrepreneurship and learning in heterogeneous cities. Incumbent residents limit city expansion through planning regulations so that commuting and housing costs do not outweigh productivity gains. The model builds on strong microfoundations, matches key regularities at the city and economy-wide levels, and generates novel predictions for which we provide evidence. It can be quantified relying on few parameters, provides a basis to estimate the main ones, and remains transparent regarding its mechanisms. We examine various counterfactuals to assess quantitatively the effect of cities on economic growth and aggregate income.
In the 1920s, the United States substantially reduced immigrant entry by imposing country-specific quotas. We compare local labor markets with more or less exposure to the national quotas due to differences in initial immigrant settlement. A puzzle emerges: the earnings of existing US-born workers declined after the border closure, despite the loss of immigrant labor supply. We find that more skilled US-born workers – along with unrestricted immigrants from Mexico and Canada – moved into affected urban areas, completely replacing European immigrants. By contrast, the loss of immigrant workers encouraged farmers to shift toward capital-intensive agriculture and discouraged entry from unrestricted workers.
We also discuss her broader body of work on the age of mass migration. At the peak of this era, the United States had a foreign-born population of 15%. Today, after a century of restricted immigration, the United States foreign-born population has only just returned to 15%.
It’s a fascinating discussion with special relevance to today’s debates about immigration.
Car exhaust is a major source of air pollution, but little is known about its impacts on population health. We exploit the dispersion of emissions-cheating diesel cars which secretly polluted up to 150 times as much as gasoline cars across the United States from 2008-2015 as a natural experiment to measure the health impact of car pollution. Using the universe of vehicle registrations, we demonstrate that a 10 percent cheating-induced increase in car exhaust increases rates of low birth weight and acute asthma attacks among children by 1.9 and 8.0 percent, respectively. These health impacts occur at all pollution levels and across the entire socioeconomic spectrum.