Ambition and leadership qualities will make or break a United States president, and likewise, the nation, according to a man who has served under four presidents.

“Leadership is the X-factor in human affairs,” David Gergen said Sunday night at Kansas University’s Lied Center. “Individual leaders matter.”

Gergen, former adviser to Presidents Richard Nixon, Gerald Ford, Ronald Reagan and Bill Clinton, discussed the good and the bad leadership qualities he saw in the White House as he spoke during the third presentation of the Dole Institute of Politics 2003 Presidential Lecture Series.

About 1,800 people showed up to listen to Gergen, Lied Center officials estimated. Lawrence resident Nancy Helmstadter, celebrating her 73rd birthday, was one of them. She was not disappointed.

“It was the most outstanding, invigorating talk I’ve heard in a long time,” Helmstadter said of Gergen. “I wish I’d had a college professor like him.”

Joanne Feist, 66, Lawrence, agreed. “I just happen to agree with everything he said, which is kind of unusual,” she said.

Gergen, currently an editor at-large for the news magazine U.S. News & World Report and professor at the John F. Kennedy School of Government at Harvard University, described Nixon as a long-range strategist. Nixon thought that by driving a wedge between the Soviet Union and the People’s Republic of China the demise of communism would eventually follow, Gergen said. Nixon supplied the wedge by opening relations with China, he said.

“It was the beginning of the end of the Cold War,” Gergen said.

Nixon was not a brilliant man, but he was well-read and noted for waking up in the middle of the night to read books, Gergen said.

Richard Norton Smith, director of the Dole Institute of Politics, left, speaks with David Gergen, editor at-large for U.S. News & World Report, as they walk to the backstage area of the Lied Center just before Gergen's speech. Gergen, the third speaker in the 2003 Presidential Lecture Series, spoke to a packed house Sunday night.

Nixon, who resigned the presidency in 1974 because of the Watergate scandal, also had a dark side, Gergen said.

“He basically had demons inside him,” Gergen said. “He thought the world was out to get him.”

Ford, on the other hand, brought humility and civility to the White House, Gergen said.

“This was the most honest White House I can remember,” Gergen said.

Reagan projected a confidence that was contagious to the country, Gergen said.

“I’m nostalgic for ‘the Gipper,'” he said. “He was a happy American and he made us smile again.”

Clinton was a “terrifically smart” person, Gergen said. He also described Clinton as having “360-degree leadership” because he wanted to know what people from all walks of life were thinking.

But Clinton had a lack of balance to his qualities that got him into trouble, Gergen said.

“So often he lacked a true north,” Gergen said. “You do need a compass. You do need points to guide yourself.

Although he has not served under President George W. Bush, Gergen offered a mixed opinion on the nation’s current leader. Although Bush showed his leadership abilities after the terrorist attacks of Sept. 11, 2001, he failed to grasp the complexities of Iraq, Gergen said.

“The jury is still out,” he said of Bush’s abilities.

Dave Van Hee, 53, of Lawrence, welcomed Gergen’s candor.

“I was happy to hear some muted criticism of George Bush,” he said.

Gergen received a standing ovation from the audience after his speech.