Rudolph W. Giuliani is considered by history to be one of the most successful mayors of New York City, a job many political pundits consider the hardest job in the U.S. He certainly was the greatest mayor in the history of the Big Apple since the great Fiorello LaGuardia. However, he proved an utter failure as a Presidential candidate in the 2008 Republican primaries.Giuliani made his reputation during the Ronald Reagan administration as the U.S. Attorney for the Southern District of New York, Giuliani became the most famous mob-buster since Thomas E. Dewey, the former governor of New York State and two-time Republican nominee for President of the U.S. (1944 and 1948). Giuliani's reputation as a master administrator was solidified by his staunch handling of the City after the 9/11 terrorist strikes, which could have plunged the Greater Metropolitan New York City area into chaos with devastating national effects. In contrast to the handling of the Hurricane Katrina disaster in New Orleans by local, state and federal officials, Giuliani guided the city and -- in tandem with President George W. Bush -- the nation, through the difficult weeks that followed the collapse of the World Trade Center.Giuliani, a liberal Republican, made a very poor showing in the 2008 race for the Republican Presidential nomination. His career is hardly through, and history has yet to write its final pages on the former mayor of New York City.