© 2015 Macmillan Publishers Ltd. The issue of misperception is at the heart of one of the key debates in the international relations literature about revolution and its effects on the international system. Establishing that a misperception occurred, and then led to a certain foreign policy action, is almost inevitably subjective. But one potential plausibility probe is to look to the consistency of the policies of status-quo powers toward a revolutionary state as one indicator of the importance of misperception in their policies. If the status-quo leaders overestimate the threat of revolutionary 'export', it is logical to assume that the specific actions of the revolutionary state itself would not matter that much to them. They would be fixed in their perceptions of the hostility of the new revolutionary regime, no matter what it did. Their policies toward it would be consistent over time. If, however, the status-quo leaders' policies toward the revolutionary state changed over time, in reaction to both the behavior of the revolutionary state and the reverberations of the revolution in their own societies, the argument that the threats from the revolutionary state toward the status-quo states were real would receive at least partial support. This article uses the reactions to the Iranian Revolution in Iraq and Saudi Arabia as a preliminary test.