And it has nothing to do with his drag photos...
http://www.salon.com/opinion/feature/2007/03/13/swiftboat_rudy/Giuliani's supporters believe it would be impossible to undermine the ingrained perception of their candidate as a national icon, Rudy the Rock. But imagine what a talented and aggressive Democratic media consultant could do with Giuliani's real 9/11 record. Imagine Rosaleen Tallon and a Greek chorus of angry, bereaved New Yorkers in a spate of heart-tugging commercials. The ads could include not only the family members of men and women killed on 9/11, but also hard hats sickened by prolonged exposure to the toxic ground zero air that Giuliani declared safe to inhale within days of the attack. And the chorus could include the mayor's downtown constituents, who were left to rid their homes of chemical dust without city assistance, risking their own well-being. The New York City government now estimates that 43,000 people have significant 9/11-related health problems. Many, no doubt, would gladly go on camera.
Giuliani's vulnerability can be detected, in part, in his shifting accounts of his actions. He has said, for example, that technology for police-fire interoperability didn't exist at the time the planes slammed into the towers. A fawning 9/11 Commission swallowed that line, but the U.S. Conference of Mayors found shortly before Giuliani's testimony to the commission that of 192 cities it evaluated, three-quarters had radios interoperable across police and fire departments.
Giuliani has also said that firefighters remained in doomed towers because they, as a breed, are wired to their bones and sinews to stand their ground. But firefighters are also part of a quasi-military chain of command and are wired to obey orders during a crisis -- if they can hear them. Tellingly, Giuliani's Republican successor, Michael Bloomberg, who took office in January 2002, had little difficulty outfitting the FDNY with reliable radios, which they now carry with them into harm's way.
"He tells filthy lies, shamelessly parlaying his failures into a multinational empire and national campaign," said Sally Regenhard, the mother of a fallen firefighter. He cut and ran, she says. "All the heroes of 9/11 are dead or wounded, spiritually, emotionally or physically."