The relationship between ideology and learning remains insufficiently theorized and sparsely investigated in the learning sciences. Drawing on Stuart Hall's theorization of ideology, Judith Butler's notion of the (un)grievability of lives, and Sara Ahmed's construct of stickiness, we illustrate how insights from critical social theory are indispensable to understanding processes of learning and how perspectives from the learning sciences can enrich critical social theory. Through the analysis of a classroom discussion on the use of militarized drones in an undergraduate engineering ethics course, we show how ideological convergence among participants constructed locally significant categories of "civilian," "terrorist," and (un)grievability, which narrowed the possible trajectories for students' disciplinary learning in engineering and engineering ethics. Our analysis also shows that fleeting moments of ideological expansion offered opportunities for new learning; however, most of these instances of possibility were not sustained through the classroom discussion. We explicate how ideological convergences and expansions, as interactional achievements, profoundly matter for disciplinary learning and students' identities. In conclusion, we explore the implications of our findings for broader contexts of learning and for the field of the learning sciences.