Why did the League of Nations fail in its attempts to keep peace?

Membership

When the League was created, there were 42 original member countries. By 1930, membership had increased to nearly 60. However, at any one time, several of the larger and more powerful nations were not members, including:

• the USA, who refused to join.
• the defeated nations (including Germany) who, at first, were not allowed to join.
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