This article explores the extent to which ‘transnationalism’ offers analysts a meaningful prism through which to analyze racially or ethnically motivated violent extremist (REMVE) terrorism or whether the term obscures more than it illuminates. The ‘transnational’ dimension of REMVE terrorism is often ill-defined and misunderstood, leading to misconceptions about the nature of such networks that in turn exaggerate their ‘global’ reach and distort our understanding of how they operate in practice. The digital revolution has internationalized far-right extremist networks, but many of these remain regional rather than truly transnational. Nevertheless, understanding the transnational dimension of social media and its role in the radicalization of lone-actor REMVE terrorists is increasingly important. Online REMVE communities rather than physical organizations per se serve as the medium through which violent ideologies are spread; where lessons from previous attacks are learned and internalized; where the perpetrators of violence are revered; and where further acts of violence are encouraged and incited—which, as this article demonstrates, has real-world effects. What this suggests is that, insofar as REMVE terrorism is concerned, ‘domestic’ terrorism is increasingly inseparable from tackling ‘transnational’ terrorism and that digital platforms have increasingly blurred the boundaries between the two.