Today's expected grand jury indictment of vice presidential aide Lewis Libby reflects character flaws in George W. Bush, as well as a chronic pattern of missteps characteristic of recent second-term presidents, Duke University historian William Chafe says.

"Political debacles like this can be traced back to personality traits of presidents," said Chafe, the author of "Private Lives/Public Consequences."

"Two traits dominate the Bush personality: a passionate devotion to an inner circle of friends and allies (sometimes called 'cronies'); and a singular self-certainty, rooted in his 'born-again' religious conversion, that his is the only way, and you are either for us or against us," Chafe said.

Both traits can be seen in today's expected federal indictment, said Chafe, the former dean of Arts and Sciences at Duke. "Joseph Wilson had the temerity to criticize Bush's policy in Iraq -- a 'no-no' given Bush's conviction that the Iraq war was righteous and necessary - and, consistent with Bush's determination to punish his foes, his inner staffers set out to retaliate against Wilson."

Chafe, a former president of the Organization of American Historians, also noted that Bush's recent problems fall into a pattern that has afflicted other second-term presidents.

"Franklin Roosevelt's massive New Deal majority fell apart when he tried to 'pack' the Supreme Court; LBJ's overwhelming re-election mandate became a victim of growing sentiment against the Vietnam War; and Ronald Reagan's decisive victory in 1984 was followed by the Iran-Contra affair and the rogue behavior of a few White House staffers. There is a remarkable similarity in all of these cases to what is happening today -- witness the fate of Bush's proposals to transform Social Security, the growing unpopularity of the war in Iraq and the current problems among White House staffers.

"Perhaps the most important lesson a second-term president can learn," Chafe concluded, "is to act humbly, listen to critics and avoid self-destructive behavior."