Trust strengthens people's confidence in a stable society and their willingness to perform pro-social behaviors, such as getting vaccinated or protecting a livable climate and environment. This review proposes a framework of how norms of trust change during times of uncertainty and collective threat. Norms of trust influence expectations toward another's actual or acceptable behavior in interdependent contexts and thus inform an individual's level of trust. These expectations are based on experienced behavior, norm-based beliefs about the counterparty, and/or projections about what oneself would do in a given situation. A match or mismatch between expectations and the experienced behavior of others (both individuals and institutions) during interactions in new environments either affirm or weaken norms of trust.