New Delhi, May 9 -- Australia's national security establishment is facing one of its most politically charged moments since the collapse of the Islamic State caliphate, as the return of ISIS-linked Australian women from Syria collides with an expanding inquiry into the Bondi Beach terror attack and renewed scrutiny of the country's counterterrorism strategy.

The debate intensified this week after several Australian women and children linked to former ISIS fighters arrived back in the country from detention camps in northeastern Syria, where many had spent years living under Kurdish administration following the territorial defeat of the Islamic State. Within hours of landing, three women were arrested and charged with terrorism-related of...