A considerable amount of research in the field of International Relations (IR) has acknowledged the
interplay between domestic politics and foreign policy. Few studies, however, have investigated this phenomenon
in the narrower field of transboundary water politics. There is also a general lack of research exploring how the
formation of a national identity can overlap with the construction of a large hydraulic infrastructure, and how this
can have repercussions at the international level. This paper draws on Robert Putnam’s (1988) two-level game
theory to illustrate how the interrelation between the domestic and the international dimensions matters in
transboundary water politics. Perspectives from IR, political geography, and water politics serve to present a
conceptual framework which is then linked to studies on nationalism. This helps to highlight the analytical
relevance of such a perspective to understand the issue of large dams. The paper takes the cases of the Grand
Ethiopian Renaissance Dam in Ethiopia and the Rogun Dam in Tajikistan as examples