Social-media companies make extensive use of artificial intelligence in their efforts to remove and block terrorist content from their platforms. This paper begins by arguing that, since such efforts amount to an attempt to channel human conduct, they should be regarded as a form of regulation that is subject to rule-of-law principles. The paper then discusses three sets of rule-of-law issues. The first set concerns enforceability. Here, the paper highlights the displacement effects that have resulted from the automated removal and blocking of terrorist content and argues that regard must be had to the whole social-media ecology, as well as to jihadist groups other than the so-called Islamic State and other forms of violent extremism. Since rule by law is only a necessary, and not a sufficient, condition for compliance with rule-of-law values, the paper then goes on to examine two further sets of issues: the clarity with which social-media companies define terrorist content and the adequacy of the processes by which a user may appeal against an account suspension or the blocking or removal of content. The paper concludes by identifying a range of research questions that emerge from the discussion and that together form a promising and timely research agenda to which legal scholarship has much to contribute.