Josh is an internationally recognised authority on the role of masculinities in violent extremism and terrorism and the attraction of men to far-right populist and nationalist movements. An author of three books on the topic, Josh has conducted research on mens attitudes to women, minorities, emotions, and violence across a wide variety of contexts from Australia, the United Kingdom and United States to Russia, India, and the Philippines. He is currently involved in two major research projects funded by the Australian Research Council examining the role of masculinities in the Australian Far Right and pathways and patterns of participation by men in Anti-Women online movements. A third current project is funded by the E-Safety Commissioner examining boys use of the internet. 

He has presented his work on masculinities and violent extremism to a variety of international organisations and universities including the United Nations Development Program, North Atlantic Treaty Organisation (NATO), Nordic Network on Masculinities and International Centre for Counter Terrorism (ICCT) - the Hague, whilst advising both State and Federal Government Departments on violent extremism and emerging threats in Australia. Josh has held visiting positions at Harvard, New York University, and a visiting fellowship at Oxford. His research and comments have been cited across a variety of international media outlets including the New York Times, BBC, Al Jazeera, The Guardian, Sydney Morning Herald, and ABC.