Why is this useless UN still around?

the United Nations has five nations that can veto any resolution that the majority of the U.N. members agreed upon.  The countries with this veto power are China, France, Russia (formerly the Soviet Union), the United Kingdom, and the United States of America.  These countries have this power because they were the founding countries of the United Nations that wrote the rules for the U.N. after World War 2.  Unfortunately, this non-democracy fails for several reasons.  First, only a true democracy among nations is unbiased and fair.  Thus, the complete structure of the U.N. needs a major overhaul.  This too is not likely to happen, since the countries with vetoing power are unlikely to unanimously agree to give up this right for fairness sake.