Lydia Khalil is a Research Fellow at the Lowy Institute and an Associate Research Fellow at Deakin University. She began her counterterrorism and national security career after the September 11th attacks. She is a recognised expert on terrorism and extremism, having worked for the White House Office of Homeland Security, US Department of Defense, the New York Police Department, Boston Police Department and the Council on Foreign Relations. She is a frequent media commentator and has been widely published.