International political factors of the union of states under one umbrella

We can rarely see the examples of successful alliances through the world history. After the WWII, creation of alliances was one of the trustful ways. Though, unsuccessful alliances and international organizations also had their roles, for example Nations League. Those examples refined systems and every new union formed more assertively. The meaning of this union is that independent ones unite their resources, for reaching the mutual goals together. Also main point of this union is to take care of security. We should underline the fact that every joint country has different reasons such as political, economical, regional issues and others. Important benefit of joining of every state for one goal brings incumbent balance of strength.