“We need a national debate on nicotine,” said Mitch Zeller.

Zeller is the director of the Center for Tobacco Products, a division of the Food and Drug Administration created in 2009 when Congress passed legislation giving the F.D.A. regulatory authority — at long last! — over cigarettes. In addition, the center will soon have regulatory authority over other tobacco products, including electronic cigarettes, which have become enormously controversial even as they have gained in use. Through something called a “deeming rule,” the center is in the process of asserting that oversight over e-cigarettes.

Opponents of electronic cigarettes, which include many public health officials, hope that the center will treat these new devices like it treats cigarettes: taking steps to discourage teenagers from “vaping,” for instance, and placing strict limits on the industry’s ability to market its products.

Proponents, meanwhile, hope that the center will view e-cigarettes as a “reduced harm” product that can save lives by offering a nicotine fix without the carcinogens that are ingested through a lit cigarette. In this scenario, e-cigarette manufacturers would be able to make health claims, and adult smokers might even be encouraged to switch from smoking to vaping as part of a reduced harm strategy.

When I requested an interview with Zeller, I didn’t expect him to tip his hat on which direction he wanted the center to go, and he didn’t. Indeed, one of the points he made was that the F.D.A. was conducting a great deal of scientific research — more than 50 studies in all, he said — aimed at generating the evidence needed to better understand where to place e-cigarettes along what he calls “the continuum of risk.”