This study draws on the "cascading activation" model of press-state relations to explore U.S. political and news discourse
surrounding the 1968 My Lai Massacre. We systematically analyze White House, military, congressional, and news communications
and draw upon scholarship in social psychology to assess why the press might challenge certain frames in response to My Lai
but indiscriminately echo others. In particular, within these communications, we examine how serious and widespread the actions
at My Lai were conveyed to be, how the circumstances were portrayed, how the actors involved in the incident were characterized,
and the extent to which America’s core values were questioned. Our findings suggest that the Nixon administration employed
frames designed to downplay the severity of the My Lai incident, highlight extenuating circumstances faced by those directly
involved, denigrate the alleged low-level perpetrators, and bolster the national identity. These frames were then largely
echoed in the press, despite consistent and forceful challenges by congressional Democrats. These findings, we argue, align
with the cascading activation model, and we build on it by highlighting the underlying importance of "cultural resonance"
in the framing process. We reflect on the theoretical and practical implications of these patterns and, in doing so, engage
the broader scholarly debate over the process through which U.S. news coverage aligns with the communications of government
officials, particularly in moments of national dissonance.