Why? Human beings got along for many thousands of years without a world body — in fact right up until the League of Nations formally began on January 10, 1920. The United Nations is nothing but a revamp of the League, which turned its assets over to the UN on April 18, 1946.
So, in the 84 years since 1920, what has the world body accomplished? Did it prevent WWII? Or Stalin's and Mao's mass starvation of their own people? Or, for that matter, prevent the spread of Communism into China, North Korea, Vietnam, Cuba, Africa and elsewhere? Has it stamped out slavery in those areas where it still exists? For every dollar spent on programs to help fight poverty and famine in the third world, how many dollars went to line the pockets of UN bureaucrats and the big shots in their home countries? Has it helped resolve the Israeli-Arab conflict? Or prevented any war, anywhere? Or any genocide?
Other than being a sometimes useful tool to contain the Soviets during the Cold War, what useful purpose has the UN ever served? How much corruption has gone uncovered until this oil-for-food scam?