One of the more amusing perennial cries from the stiffies is "GET US OUT OF THE UN!!!", or something to that effect. This is usually followed by some mutterings like "they couldn't disarm Saddam, we had to do that alone!" or "we'll never turn the sovereignty of the USA over to the French and Germans!".
While far from perfect, the United Nations is a necessary and often effective organization (it would now appear that UNSCOM, and later UNMOVIC were quite effective in Iraq prior to the invasion). It is not an aggressive military powerhouse, but it is not meant to be. It is, however, a very competent provider of aid and comfort around the globe, as well as a forum to resolve disputes. Its the only vehicle which allows the most countries to formally communicate on a regular basis. At its worst, the UN is harmless, benign. At its best, it represents great hope, where there previously was none.
As with most simplistic rightie battle cries, the one about US sovereignty is misguided and misleading (as was done effectively during last year's presidential campaign where POTUS attempted to mislead the public about John Kerry by repeating the "global test" statement). The UN is not a world government with its Secretary-General as the President, wielding significant global power. It is more like a combination of a homeowners' association and a service organization. The real power in the UN rests with the Security Council, and specifically with the 5 permanent SC members (which includes the US). Any significant decision made by the UN has to be approved by at least 9 members of the UNSC, and has to be unanimous among the permanent 5. Any one of the 5 can kill the deal. Besides, whenever the US disagrees with the world, we just pick up our toys and go home anyway, so what are we worried about?