How do realists explain cooperation between countries?

In the context of international relations, realists generally view the international system as an anarchic environment—meaning there is no central authority to enforce rules or arbitrate disputes. Because states must prioritize their own survival and security in this "self-help" system, cooperation is often viewed with skepticism.12

However, realists do explain cooperation through several key lenses:

• Balance of Power: Realists argue that states may form alliances and cooperative arrangements to maintain a balance of power, which helps prevent any single state from becoming too dominant and threatening the security of others.32
• National Interest: Cooperation is not driven by altruism but by the pursuit of national interest. States cooperate when it is useful to their own security or economic goals.12
• Hegemonic Stability: According to hegemonic stability theory, a dominant state (a hegemon) may underwrite the stability of the international system by formulating rules and providing security. In this view, international institutions often reflect the interests and power of the leading state, and cooperation persists as long as it serves the hegemon's interests.413

While neorealists acknowledge that states can cooperate, they remain cautious, emphasizing that such arrangements are often fragile and subject to the underlying distribution of power.32