Last week the Food and Drug Administration filled the regulatory vacuum surrounding electronic cigarettes, battery-powered devices that convert a solution of nicotine into a vapor.

The agency draft regulations would ban sales to youths but allow flavorings and set a two-year timeframe for approval of existing vapor products.

Growing in popularity among smokers—about one in five tried an e-cigarette between 2010 and 2011, the latest years for which the Centers for Disease Control has data—the current market is estimated at $2.2 billion in the U.S., up from under $1 billion two years ago.

Reactions to the agency’s draft proposal prompted a fresh round of nervous commentary on the devices. And, much of it, though by no means all (the New York Times is a refreshing exception), gave greater consideration to the speculative harms surrounding e-cigarettes than to their considerable potential for benefit.

A recent article in The New Republic by pediatric cardiologist Darshak Sanghavi gave disproportionate weight to e-cigarette skeptics’ unsubstantiated claims. We felt a more detailed picture was warranted.