Realism approach was dominant theoretically during the cold war. Realism portrays international affairs as the pursuit for power among self-centred states that is a cynical representation of prospects that mitigate war and conflict (Jervis, 2005). Realism approach was dominant during the cold war since it offered powerful and easy definitions of imperialism, alliances, war and other international events. Realism adopted a consistent competition analysis that was fundamental in the American-Soviet conflict.
Challenges to realism originated from liberal theories. Liberalism argued that interdependence on the economy discouraged nations from using force because warfare threatens prosperity of all sides (Jervis, 2005). The other school of thought argued that the manifest democracy derived peace across the world based on the claim that democratic states were peaceful compared to authoritarian states. The third school of thought believed that international institutions could encourage nations to forego gains that were greater than cooperation (Jervis, 2005).
While liberalism and realism focused on factors that led to material growth such as trade and power, constructivist approach concentrated on the effect of ideas (Jervis, 2005). Constructivist theories do not assume that states seek survival only. Ideally, these theories argue that states are a product that is malleable for historic and specific processes. The approach pays more attention on the root course of a change compared to liberalism and realism.