Absolutely. A UN without the US is irrelevant anyway, all modesty aside. It's just a fact, sorry.
Besides I'm sure many nations that value freedom and democracy as does the US would jump ship with us and form the beginings of a new world organization, one with a bit higher standards and responsiveness.
Yes sir. I'll take Britain, Australia, Poland, Japan, Taiwan, Israel, and the Dutch over the rabble at the UN any day.