| It's just how things work. The League of Nations failed largely because it lacked the participation and support of major powers. The United States, despite being a principal architect of the League, never joined [1]. This lack of participation undermined the its legitimacy and effectiveness. The veto power was established at the founding of the UN in 1945 as a reflection of the state of the world following World War II. The major powers were given veto power to get their buy-in and participation. Without this mechanism, these powers might not have joined or supported the UN, undermining its formation and initial effectiveness. If the veto power were removed, the major powers might feel that their core interests and national security concerns could be overridden by the majority [2], leading to their withdrawal from the UN, and significantly weakening the organization's influence and capacity to act. There's no real authority in any of these bodies, only the appearance and illusion of legitimacy which requires buy-in from its strongest members. [1] https://history.state.gov/milestones/1914-1920/league [2] From above: > Motivated by Republican concerns that the League would commit the United States to an expensive organization that would reduce the United States’ ability to defend its own interests, Lodge led the opposition to joining the League. Where Wilson and the League’s supporters saw merit in an international body that would work for peace and collective security for its members, Lodge and his supporters feared the consequences of involvement in Europe’s tangled politics, now even more complex because of the 1919 peace settlement. |
And what actually prevented a global conflict after the world war II is not the UN succeeding into what League of nations, it is nuclear war and MAD doctrine. UN is currently a place so inneffective outside the general stuff that the veto countries can agree.
Again you are describing the current status que not how a real equal international community should work. Because currently when you hear that international community is behind <foo> it is usually US and some of their allies who are actual minority of humans [1]