Historians have rethought some of the prevailing assumptions employed in writing about the Cold War in Australia. Until recently, the history of the Cold War in Australia was often written with too little detachment and skepticism toward the Left, and with a failure of scholarly empathy toward the claims of the anti-Communist Right. The opening of new archival and intelligence sources (such as the ‘Venona’ papers) is one reason for the shift in the field. Another is a reassessment of the link between the USSR and the Communist Party of Australia (CPA), that leads to questions about the CPA’s dogmatic pro-Soviet stance, and to what degree this was partly responsible for its defeats, rather than simply victimisation. New archival sources establish that some clandestine political activity was undertaken, including espionage and that Soviet funds were given to the CPA over a long period. Not every historian, however, has embraced this new evidence. The present article critiques recent contributions by Cain and Hocking, suggesting that discussion of political fundamentalism on the Left and the security response to it is vital if Cold War history is to be understood and made relevant to discussions of contemporary terrorism.