The UN, WTO, EU, etc, are ineffective, bureaucratic messes, but no matter how bad they are, they're a better way of solving international disputes than the historical alternatives.
Western nationalists like to talk about how the cultures of the middle east are inherently violent, but seem to forget that the history of europe was a centuries-long bloodbath that eventually engulfed the entire world in horror and put us nearly on the brink of the extinction of all human life.
It's those alliances and international organizations that allowed us to step backwards from it. Solving our problems in courtrooms and at negotiating tables rather than on the battlefield.