At some point, entrusting world peace and security to one organization is too great of a task. It becomes far too difficult and far too complex to be able to place this responsibility on one organization's collective shoulders. Organizations such as the United Nations have a role and a purpose in advancing the cause and message of international security and stability. However, to be able to enforce the concept of international peace across the world is something that both politically and logistically cannot be done in an effective and worthwhile manner. Perhaps, this is where the message of globalization has its greatest resonance whereby each nation operates and functions in an interconnected manner, recognizing that the goals of peace and security are something that is in everyone's interest.
In theory, it would be nice if it could be, but there is no chance (in my opinion) that this will be able to happen in my lifetime (I'm 40). I'm not sure that it would be good for this to happen in the real world anyway.
The reason that it will not happen is that countries are really not going to be willing to give up their sovereignty. Really, this is not surprising. Would we, as Americans, like it if some international body could come in and tell us that we absolutely had to get out of Afghanistan right this minute? It's hard to imagine.
The reason that I think it should not happen is because I am not sure that it is right to give some organization the power to absolutely tell countries what to do. I do not see how an organization could, for example, decide whether Taiwan should be independent or whether it should be part of China. It's just too hard of a question and I don't see how an organization could be competent to decide those questions.
After the failure of the League of Nations, the United Nations Organization was founded in 1945 with the laudable motive of facilitating international cooperation and ensuring world peace by resolving conflict amongst the different nations of the world by peaceful means. Its considered to be a 'talking shop' where a lot of dialog is constantly going on amongst the various nations without much effective action to actually resolve international conflicts.
With so many nation states, each with its own political, economic and social agendas its too much to expect one international organization to safeguard and ensure world peace and stability.
What is really essential is that each nation must stop being selfish and realize that the world is after all a small place and that the resources of the earth are limited and finite and learn to accept cultural differences and coexist peacefully with all the other countries on this planet.