This paper addresses the implications of the transformation of the international system from a bipolar to a unipolar system for realist theory. The paper demonstrates and analyzes how realists react to this external challenge. The paper demonstrates the traditional response to the "attack" on realism, in an attempt to preserve its basic premises. It then proceeds to explain the different revisionist orientations undertaken by the theorists of this school in an attempt to harmonize the foundations of this theory with unipolarity. The study deals with four revisionist approaches: "balance of threat", "soft balance", "balance of interests" and "external balancing". This paper presents a new addition, "internal balancing" which, while derived from the liberal theory opposed to realism, comes with a realist adaptation to explain the length of the current unipolar era.