Do social media tend to promote citizen freedoms or enhance authoritarian control? Beyond their occasional role as facilitators of mass mobilization, social media platforms such as Twitter offer a daily means of anonymously voicing political opinions. As such, we would expect them to promote freedom of speech and deed through multiple channels: solving coordination problems by helping citizens learn what fellow citizens think, facilitating mass mobilization even in the face of notoriously repressive regimes, and even acting as high-frequency opinion poll data by which activists can gauge (and even shape) public opinion on various topics (Jamal et al. 2015). Yet in line with the thought that most open platforms tend to fall prey to those most organized to take advantage of them, we present evidence that social media outlets present authoritarian governments with an opportunity to influence citizen perceptions and expectations, not merely as a source of mobilization threats to be managed (King et al. 2013). We focus on major, combative hashtags linked to Saudi Arabia, Qatar, and the United Arab Emirates that emerged in the wake of the GCC diplomatic dispute that erupted in June 2017 as well as those stemming from government efforts towards domestic social and economic reform in Saudi Arabia. These regime goals are accomplished through a combination of offline coercion of online "influencers" to repeat key talking points and hashtags (Al-Omran 2017), and wielding armies of online "bots" (Jones 2015) to boost visibility of certain tweets and trends. Not only have Arab authoritarians largely survived the threats that social media initially mobilized against their rule; we argue that some – particularly Saudi Arabia and the UAE – have now turned the new tool to their favor, using it as a day-to-day means of building ideological consensus to ensure regime stability. In tracking “waves” of Twitter activity centered around particular hashtags, we find that a small minority of Twitter accounts drive a disproportionate amount of traffic in conversations criticizing Qatar’s foreign policy and questioning its domestic stability (relative to conversations reacting to widely experienced natural disasters or domestic demands in Saudi Arabia). Case studies of particular campaigns suggest a concerted effort by state security institutions, at least in Saudi Arabia, to stifle dissent on contentious issues by drowning out public evidence of shared dissent.