What role does diplomacy play in the modern world order, and what are the characteristics of a good diplomat? Which countries are the great powers today, and which will lead in 2050? Does NATO have a role in helping manage the political, economic, and military challenges facing the United States? And why is morale reportedly at a low ebb in the State Department? In this episode, former ambassador to NATO Nicholas Burns, the Goodman Family professor of the practice of diplomacy and international relations at Harvard Kennedy School, answers these questions and more, based on his long career in government service.

If judges truly are impartial arbiters of justice, why do politicians fight over who will be appointed to the bench? Are the courts actually a political prize? And are judges really akin to umpires, just calling “balls and strikes”? How does the back-and-forth between the legal profession and politicians shape the quality of nominees to the bench? In this episode, Harvard Kennedy School professor of public policy Maya Sen considers these questions as we discuss the power of the legal profession and the politicization of American courts.

No country in the world spends more on health care than the United States, or has less to show for it when compared to other wealthy nations. The U.S. spends nearly 50 percent more per capita than Switzerland, the second biggest spender among wealthy nations, but consistently ranks near the bottom on measures of population wellness and life expectancy. Is there a better system, and if so, what should it look like? What role does wasteful spending play in this equation? How much is attributable to administrative costs? In this episode, Eckstein professor of applied economics David Cutler considers these questions as we discuss the high price of American medicine.

HOW DO PRESIDENTS INCORPORATE MORALITY into decisions involving the national interest? Moral considerations explain why Truman, who authorized the use of nuclear weapons in Japan during World War II, later refused General MacArthur’s request to use them in China during the Korean War. What is contextual intelligence, and how does it explain why Bush 41 is ranked first in foreign policy, but Bush 43 is found wanting? Is it possible for a president to lie in the service of the public interest? In this episode, Professor Joseph S. Nye considers these questions as he explores the role of morality in presidential decision-making from FDR to Trump.

We’re delighted to bring you Season Two of Ask a Harvard Professor. Each week, two of our editors, Jonathan Shaw and Marina Bolotnikova, will interview some of the world’s most prominent scholars and discuss pressing ideas heading into the 2020 presidential election. Join us for podcasts with Nicholas Burns on American diplomacy and Maya Sen on the politicization of the U.S. court system, among several others. We look forward to sharing these conversations with you.

What does hiphop culture—rap music, break dancing, and graffiti—have to do with Harvard? In this episode, Monrad professor of social sciences Marcyliena Morgan explains that hiphop began with the children of people who marched in the civil-rights movement: teenagers taking apart their parents’ jazz recordings and expressing their distress with a world that hadn’t changed for them, despite their parents’ efforts. They made a new urban poetry of social dislocation, set to music. Now the movement is pushing change in the broader culture, and a Harvard archive seeks to document its beginnings and significance.

What makes a photograph art? A great photograph may be the result of artistry, or it may be the result of dumb luck: a fleeting, perfect composition captured by chance. At a time when there is a camera in every pocket, how do curators distinguish between documentary and artistic work? In this episode, Burden professor of photography Robin Kelsey, the dean of arts and humanities, explores the role of chance in artmaking generally, and in photography in particular.

Cities are an integral part of Earth’s future: by 2050, 68 percent of the world’s population will be living in an urban area. Solutions to social problems, from climate change to poverty, will therefore be tied to the fates of cities. In this episode, Glimp professor of economics Ed Glaeser explains why he is overwhelmingly optimistic about urban growth. Cities, he says, are engines of innovation and economic activity that create opportunity. “Humans are a social species that gets smart,” he explains, “by being around other smart people.” When they do, their impact on the planet’s climate is lessened in surprising ways—and in surprising places across the United States.

Mass murders committed with firearms are becoming more frequent In the United States. And the total number of gun deaths, a majority by suicide, is now on par with those caused by automobile accidents. None of this has broken the political gridlock in Washington that surrounds the issue of gun control. In this episode, professor of health policy David Hemenway describes public-health strategies that can save lives, often without political intervention, by making guns inherently less dangerous, and by enlisting gun advocates and gun-shop owners in efforts to reduce fatalities.

Weed, ganja, pot, flower, dope, grass, bud: marijuana has many names, but an even greater number of chemical constituents, from THC, the psychoactive component, to cannabidiols such as CBD, often touted for its therapeutic potential. In this episode, Dr. Staci Gruber, an associate professor of psychiatry at Harvard Medical School who directs the longest-running study of medical cannabis use in the United States, discusses the effects of the plant’s components on human health. At a time when access to marijuana is progressively legalized, Gruber lays out the surprising ways in which its cognitive effects differ between youths and adults, and between medical marijuana patients and those who use the drug recreationally.