Abstract-It is widely acknowledged that cultural diversity is a critical aspect of public diplomacy seeking to communicate with international publics. However, little research-based evidence exists about what cultural diversity means to practitioners. This study examines how the attributions of cultural identity are negotiated in the direct and dialogical (online) conversations among the U.S. Embassy and Chinese netizens. It captured and analyzed 1,239 tweets and all the comments that appeared under the Weibo (Chinese version of Twitter) handle of the U.S. Embassy during the observation period. Within the framework of constructionism theory and intercultural public relations, this article asserts that, in a cross-situations where the external publics whose cultural identifications differ from those of the organization, issues representing cultural conflicts may arouse more negative responses. Findings indicate that compared to neutral topics, conflict-related information correlates with a higher proportion of negative comments. Therefore, this study shed light on the understanding of the power of the situational theory in predicting which issues are likely to create active publics.