What are the effects of anarchy in International Relations?

The most relevant theory regarding anarchy in the world order is realism. Realism posits that because there is no overarching order and law in the world, each individual state tries to maximize its power relative to all other powers. After all, with no institution above the state to save it, the state must ensure its ability to survive as existing is a prerequisite to doing anything else. This leads to a number of things but there are a few scenariOS in particular worth mentioning. First, this can lead to a situation known as the security dilemma. To quote Shiping Tang, "Under a condition of anarchy,two states are defensive realist states-that is, they do not intend to threaten each other's security.31 The two states, however, cannot be sure of each other's present or future intentions. As a result, each tends to fear that the other may be or may become a predator. Because both believe that power is a means toward security, both seek to accumulate more and more power. Because even primarily defensive capability will inevitably contain some offensive capability, 32 many of the measures adopted by one side for its own security can often threaten, or be perceived as threatening, the security of the other side even if both sides merely want to defend their security. Consequently, the other side is likely to take countermeasures against those defensive measures. The interaction of these measures and countermeasures tends to reinforce their fears and uncertainties about each other's intentions, leading to a vicious cycle in which each accumulates more power without necessarily making itself more secure, through a self-reinforcing or positive feedback mechanism." Another effect is counter-balancing in which coalitions of powers form alliances to balance against rising hegemons to check their power.