Why did the League of Nations promote disarmament?

The League of Nations promoted disarmament primarily because it was widely believed that the massive buildup of armaments by European great powers in the period leading up to World War I was not merely a consequence of international tension, but a direct cause of the hostility and war that followed.12

The organization viewed disarmament as a fundamental component of its mission to ensure global peace and security. Within the Covenant of the League of Nations, members committed to reducing their armaments to the lowest possible levels, suppressing the negative effects of private arms manufacturing, and exchanging information regarding their military programs.3

The League operated under the doctrine that security and disarmament were mutually dependent: increased security was considered a necessary condition for disarmament, while general disarmament was viewed as a necessary condition for lasting security. By pursuing these goals, the League sought to replace the competitive arms race with a system of collective security and international cooperation.4152