That's exactly why they continue to have the problem.
They're part of the problem, not the solution. They have no oversight, no disciplinary program and have always had a system of preferential treatment (the higher you are on the UN food chain, the more likely your misdeeds will be swept under the rug) and corrupt member states. UN observers, troops, staffers and aid workers are routinely accused of, and frequently caught skimming funds, traffiking in human slaves, running weapons, the drug trade...all the things you find in the unstable countries they're supposed ot be stabilizing.
The United States has to take the initiative in these world actions and completely bypass the U.N. at all times. The more we distance ourselves from them, when we prove to the world that the U.N. is irrelevant, we can dismantle the institution and finally get to the meat & potatoes of the world's problems.