Amos, I think your "capitalism will bring peace" idea rather absurd. Capitalism is the engine that drives the war machine.

The UN may not be the organization which ultimtely is able to transcend nationalism, war mongering, economic disparity, etc. but it is the major transitional body that will give birth to the institutions which WILL allow humanity to transcend the corporate/capitalist state and the nation state, and all the war mongerers who are clinging to their life raft.

The world will change because the majority of human beings on the planet are already demanding it, and more and more human beings are dedicating their lives to working on transforming the world on precisely that level.

I'm not saying it will happen in our life times, but it easily could happen in our children's life times.