Kallenborn is an adjunct fellow (non-resident) with the Center for Strategic and International Studies (CSIS), policy fellow at the Schar School of Policy and Government, fellow at the National Institute for Deterrence Studies, Research Affiliate with the Unconventional Weapons and Technology Division of the National Consortium for the Study of Terrorism and Responses to Terrorism (START), an officially proclaimed U.S. Army "mad scientist," and national security consultant. He has published more than 60 articles in a wide range of peer-reviewed, wonky, and popular outlets, including the Brookings Institution, Foreign Policy, Slate, DefenseOne, War on the Rocks, the Modern Institute at West Point, Terrorism and Political Violence, and Parameters. Journalists have written about and shared that research in The New York Times, the AP, NPR, The Economist, Forbes, Popular Mechanics, Politico, Al Jazeera, The Independent, Blick, Newsweek, New Scientist, MIT Tech Review, WIRED, and the BBC, among others in dozens of languages.