Realism is regarded as one of the most influential theories in international relations. Reasons of the maintaining importance for Realism; philosophical foundations, the balance of power and involving of the strong criticism against liberalism. The founder fathers of classical realism are E. H. Carr and Hans Morgenthau.

We can see differences between the realist thinkers. Therefore, their contributions, views and ideas are very significant.

According to classic realism, the concept of power and hereof, national power have a crucial value in the international politic area. The power of states and owned by the state of capacities have an utmost importance.

E.H. Carr and H. Morgenthau marked 1960s years with their studies. The common aspect of their studies; for understanding international relations, should be addressed the power policy and power factor. Also, the emergence of the studies, history is a substantial factor. Because, Carr’s views are related to the realism between the two wars (the first world war and the second World war), on the other hand Morgenthau put forward views about realism after the second World war.

Realist thinkers say that, the aim of states is desire to achieve maximum power, and they try to interfere with each other, because of the aim; at the same time the balance of power occurs and it is an important stabilizing factor.

E.H. Carr lays emphasis on the importance of the power in his book ‘The Twenty Years Crisis (1939)’. According to him, for understanding the conflicts and wars, should be analyze imbalance of power distribution. Carr describes the first world war like that, the states were doing defense for security concerns. However, after a while, they started to gain territory attacks to other states. There are states which want to increase their own power, so the national interests of the state will be conflict between each other.

In other respects, Carr looks up politics than ethics. Because powerful people become executives and weak people become ruled. Therefore, people try to reach the power.

On the other hand, According to Morgenthau, the power is a means which realizes the main goals of politics and the power forms basic instinct of political behavior.

Morgenthau says that; national power, consists of quantitative and qualitative elements. Geography, natural sources, industrial capacity, degree of military preparations, and population are quantitative elements. On the other side, national morality, national character, the quality of diplomacy and quality of the government are qualitative elements.

According to Morgenthau, international politics is a power struggle between interstate and the struggle is normal, inevitable and acceptable. In the system, radical changes are doomed to fail. National interest may chance according to current circumstances and decision makers are rationalists. The peace does not here to stay, and the balance of power is an important factor for balance of the system.

As a result, E.H. Carr thinks that, international system takes form with facts and rules of the power and he distinguishes the concept of power from states and other all of factors. On the other hand, Morgenthau thinks power is an ends of international politics and power is a means of attain it’s the ends.