You guys often forget that the UN was, basically, an US idea with the intention of maintain a stable world order and preventing another world war.
The ideas behind the UN can trace back to every type of successful international organization or treaty system in all the years that preceeded it.
Ok, so the Security Council doesn't always work- but that's because it was felt that it was better of the major powers to come together at a table and work out their differences or share common policies rather than go it alone. This is especially relevant in a nuclear age.
Then you got organizations ranging from the WHO, the UN High COmmissioner for Refugees (and how millions of refugees exist?), UNICEF, UNEP, UNDP, UNCTAD and even the world bank system works in conjunction with the UN. You have regulation on the use of the sea, on telecommunications, on space exploration, on labor and human rights standards.
As Wooz points out, the UN does a whole lot more than blue helmet peacekeeping operations. And in many of those missions it's the policies of the great powers that hamstring their effectiveness. Peacekeepers are distinctive from peacemakers. And yes sometimes it doesn't work out well, but sometimes international politics is a messy business.
The UN was a unique creation following the end of the second world war meant to stop future major wars. That, plus nuclear weapons, have generally done the job. Yes, occassionally you have humanitarian disasters and you have wars between marginal international players, but generally it keeps world peace.
Is it perfect? No. Hell, half the world suffers rampant corruption, but that's consistent with states throughout history. (For those who read, check out Tilly- statemaking and war making as organized crime- at this site-
https://toolkit.itc.virginia.edu/cg...SION:110273099913811:82151301654903/materials - which also has a lot of good academic articles on war. Give it a few minutes- CCR-there's a turkish article there and Briosa- some of this is up your ally)
Americans might consider that with the incrediable cost in lives and money and commitment of our national security assets in Iraq, (which is a minor war), it pays to have an organization that keeps the peace elsewhere.