Western scholars have long disagreed about the role that ideology played in the Cold War. The release of crucial documentation from the former East-bloc archives has shed new light on this question, but no consensus is likely to emerge. Even if all the archives are eventually opened, the new evidence will not—and cannot—provide full vindication for either realism or an ideology-based approach. A key task for scholars will be to reexamine the broad and often unspoken assumptions on which specific US and Soviet policies were based.