This study examines whether advocacy coalitions are stable over time by examining legislative hearings data concerning U.S. foreign policy and the creation of Israel. It uses content analysis of 19 different policy core and deep core belief components applied to testimonies given in 1922 and in 1944. These belief components are used to identify members of advocacy coalitions and to test the coalitions' relative stability of membership over time. In addition, this research examines the stability of the belief systems of these advocacy coalitions. It finds that the structures of the advocacy coalitions remained relatively stable, yet new components of policy core beliefs emerged among all three advocacy coalitions, and such components are converging toward the belief system of the coalition advocating for the creation of Israel.