John G. Horgan (born 1974) is a Distinguished University Professor of Psychology at Georgia State University in Atlanta, Georgia. He studies involvement and engagement with terrorism, with a focus on disengagement and deradicalisation from terrorist movements. He has been described by the European Eye on Radicalization research group as the "world’s most distinguished expert in the psychology of terrorism". Since 2019, Horgan has been leading a team of researchers funded by the U.S. Department of Homeland Security to research the incel subculture. Life and education Horgan is a native of Castleisland, County Kerry, in the Republic of Ireland. Horgan was awarded his Ph.D. in applied psychology in 2000 by University College Cork. While in Ireland, he spent several years conducting detailed research on Irish Republican movements, and published several articles on the fundraising activities of the Provisional Irish Republican Army. Research and teaching Horgan is a Distinguished University Professor of Psychology at Georgia State University, where he leads the Violent Extremism Research Group. He has previously held positions at the University of Massachusetts Lowell, Pennsylvania State University, and the University of St Andrews. While at the University of Massachusetts, Lowell he directed their Center for Terrorism & Security Studies; while at Pennsylvania State University, he directed for their International Center for the Study of Terrorism. In 2006, Horgan became a recipient of an Airey Neave Trust Fellowship Award, and he has since been awarded multiple grants for his research on terrorist behaviour. In 2010, following his consultancy work with the FBI's Behavioral Analysis Unit (BAU), he was appointed to the Research Advisory Board of the FBI's National Center for the Analysis of Violent Crime (NCAVC) until its official disbandment in 2012. In August 2012 he became a member of the new NCAVC Research Working Group. In 2019, Horgan and a group of researchers at Georgia State University were awarded $250,000 by the U.S. Department of Homeland Security to research the growth and spread of the incel subculture, a group that Horgan described as "one of the purest hotbeds of Internet radicalisation I’ve ever seen". Writing and editing Horgan has extensively researched involvement and engagement in terrorism. Some of his research on this subject was published in the journals Terrorism and Political Violence, Studies in Conflict & Terrorism, The Georgetown Journal of International Affairs, and Dynamics of Asymmetric Conflict. Horgan has written several books on terrorism, including The Psychology of Terrorism