But current and former officials said that American appeals are likely to have little effect on Gaddafi, a mercurial autocrat who for decades was regarded as a nemesis of U.S. presidents…

There is not even a U.S. ambassador at the moment. Gene Cretz, the ambassador to Tripoli, was called back to Washington recently for extended “consultations” after WikiLeaks released cables in which he described Gaddafi’s eccentricities.

“We don’t have personal relations at a high level. As far as I know, President Obama has never even talked to Colonel Gaddafi,” said David Mack, a former senior U.S. diplomat who dealt with Libya…

Still, experts say that Libya essentially floats on a cushion of oil wealth, and that any U.S. or U.N. effort to promote sanctions against it would attract little international support.