The general impression on nuclear weapons could be described as "rather useless" or "a source of destabilizing factor" in modern international relations. The negative image on nuclear weapon is already widely accepted in general public around the world. However, that would be impossible to explain the facts that more and more states are trying to develop their own nuclear ability despite of different difficulties if that impression on nuclear weapon is true. People arguing for and against the existence of nuclear weapon have their different opinion and examples supporting their own perspective. Base on this aspect, it would be an essential way for us to examine the cases of both sides, so that the negative image on nuclear arms could be determined as a truth or just propaganda for certain powers. The goal of this thesis is trying to find out the true nature of nuclear weapons in modern international relations by analyzing cases and hypotheses that is closely related to the nuclear influence in world politics. Through the analysis process on the political ability of nuclear weapons, a new aspect of viewpoint to understand the true nature of international relations would be possible