This article examines key provisions of Australia's antiterrorism legislation introduced in the aftermath of the 11 September attacks. Never before in history has Australia witnessed a comparable overhaul of national security legislation and the introduction of laws that significantly curtail civil liberties and fundamental freedoms. A question that thus needs to be addressed is whether or not Canberra's drastic legislative measures are justified by the severity of the terrorism threat to Australia. It is argued that the actual risk of a terrorism attack occurring on Australian soil is rather low. As a consequence, the Howard government's antiterrorism laws constitute a disproportionate response that has worrisome long-term implications for Australia's legal system and its society more generally.