Why do some attempts to conclude alliance treaties end in failure? From the inability of European powers to form an alliance that would stop Hitler in the 1930s, to the present inability of Ukraine to join NATO, states frequently attempt but fail to form alliance treaties. This text sheds new light on the purpose of alliance treaties by recognizing that such treaties come from negotiations, and that negotiations can end in failure. It identifies two conditions that result in non-agreement: major incompatibilities in the internal war plans of the participants, and attractive alternatives to a negotiated agreement for various parties to the negotiations. As a result, the work focuses on a group of states largely ignored by scholars: states that have attempted to form alliance treaties but failed.

Previously issued in print: 2019.

A theory of alliance treaty negotiation outcomes -- Measuring negotiations -- Analyzing negotiations -- Anglo-German negotiations -- The North Atlantic Treaty Negotiations.