Supporting the UN or Not Supporting the UN

Personally, I think we should get out of the United Nations because they haven't been able to prove they can keep conflict between their countries. Although that statement would make a lot of sense on many levels, it is also necessary for us to be there in the United Nations to help the smaller countries. They need us to help them. As the United States, we need to support the United Nations of further wars between countries. I don't see how it is hurting us, right now. "The U.S. can, at significantly less cost, wield great influence over world events and achieve U.S. policy goals by remianning fully engaged in planning and implementing UN peace operations." That is why we should stay in with the UN. Now, my theory...
I understand that if we withdrew from the UN we wouldn't be able to come back....BUT what good is it doing for them anyways. We are there, supporting them, and doing whatever we can to try to help them. Since they haven't shown that they can keep their countries in line, then what has all of our help done for them...?? NOTHING! I also think why not try something new. Withdraw from the UN and see what happens.