Abstract: Advocates for free massive open online courses (MOOCs) have heralded them as vehicles for democratizing education and bridging divides within and across countries (1). More than 25 million people enrolled in MOOCs between 2012 and 2015, including 39% from less-developed countries (LDCs) (2). But the educated and affluent in all countries enroll in and complete MOOCs at relatively higher rates (3, 4). Judged by completion rates, MOOCs do not spread benefits equitably across global regions. Rather, they reflect prevailing educational disparities between nations (see the first chart) (5). Although the global achievement gap could be caused by barriers in LDCs, such as less broadband Internet access, formal education, and English proficiency, we explore another potential but underappreciated cause. Members of LDCs may suffer from the cognitive burden of wrestling with feeling unwelcome while trying to learn and, therefore, underperform. This can be exacerbated by social identity threat, which is the fear of being seen as less capable because of one's group (6). We discuss field experiments with interventions that targeted social identity threat and caused substantial improvements in MOOC persistence and completion rates among learners in LDCs, eliminating the global achievement gap.