If two states display common behavior and attitudes toward each other without a formal agreement, what is this called?

The situation described, where two states exhibit common behavior and attitudes toward one another without the need for a formal agreement, is best characterized as a coalition. In international relations, a coalition refers to a temporary alliance of states that come together for a common purpose or to achieve a specific goal, often in response to shared interests or challenges. Unlike a formal alliance, which typically involves binding treaties and commitments, coalitions can be more flexible and may form in response to particular situations or issues.

This concept is significant in international relations as it highlights the dynamics of cooperation and conflict among states that do not necessitate formalized legal obligations. Such coalitions can emerge in various contexts, including joint military operations, humanitarian efforts, or collective responses to global issues, emphasizing the pragmatic aspects of state behavior in the arena of international politics.

The other terms, such as alliance, partnership, and confederation, imply different structures or levels of commitment that do not align with the informal and situational nature of the behavior described in the question. An alliance generally involves a formal agreement with specific obligations, while a partnership suggests a more equal relationship with shared goals, and a confederation refers to a union of sovereign states that come together for certain purposes but retains their independence. Thus