The problem, experts caution, extends well beyond Australia’s borders.

“The repatriation debate should take on a much greater sense of urgency, not only in Australia but in all countries that still have citizens and other individuals with a relationship to their home country,” Senior Director of the Counter Extremism Project, Hans-Jakob Schindler, tells the Sun.

“Having radicalized and potentially dangerous individuals under control is always better than having such individuals in a foreign country where they are not under direct control or monitoring,” Mr. Schindler explains. 

“The risk is that such individuals have knowledge about the country and can either try to return clandestinely or pass on that knowledge to other individuals that travel to Australia.”