Is the United Nations a good or bad thing in the world?

I'm questioning wether the UN is a good or bad thing. I mean it has failed at almost all of its resolutions. With Russia, France and China having veto power it gives the UN no power in Europe or Asia. all the power they can exert can only be used in Serbia(poorly), africa, and some parts of South America. I mean in Serbia French UN troops helped the Serbians slaughter hundreds of muslims just so they could land a plane.