Honestly, I don’t think the vetoes are the main issue. In international diplomacy/law, enforceability rules discussions. If all the small countries vote to prevent the US-Iran war and intervene against the US, good luck enforcing it. The vetoes just reflect this reality.
The UN helps coordinate where there is a will to cooperate, but it can’t govern the world, whether veto power exists or not. What could be done to improve this I am not sure, but it is not as simple as removing the veto.





And by that you mean America allowed it’s companies to secretly aid Hitler until Japan touched Americas boats and Hitler declared war on America?