Presidential legacies are not set in stone the day that they leave office.

According to Mark K. Updegrove, director of the Lyndon Baines Johnson (LBJ) Library and Museum, post-presidential decisions can change the way history views a president.

“It takes a long time to see the forest for the trees,” he said.

In former President George W. Bush’s case, Updegrove said that he is excited to see what Bush can do in his post-presidential life, particularly with the existing Bush Institute.

Updegrove spoke to a small, but crowded room in DeGolyer Library Monday afternoon as part of a SMU Libraries event. Updegrove is a presidential historian and has been director of the LBJ Library since October 2009.

He is the author of two books: “Baptism by Fire: Eight Presidents Who Took Office in Times of Crisis” (2009) and “Second Acts: Presidential Lives and Legacies After the White House” (2006).

Updegrove discussed every U.S. president since Harry Truman and noted that post-presidencial life has evolved. When Truman left office, Updegrove said, “He had nothing.” He had no Secret Service, no office space, no staff and no presidential pension.

But now, Updegrove explained, presidents have begun to shape their legacy by their post-presidential life.

Several years after he resigned from office, Updegrove said Richard Nixon reinvented himself and began to devote himself to causes that he felt were important, particularly foreign policy.

He was a self-appointed Secretary of State; a freelancer, according to Updegrove.

“There’s a lesson here for his successors,” Updegrove said. He explained that by concentrating on specific policies, Nixon was able to burnish his image as a foreign policy expert, rather than a disgraced president.

Jimmy Carter is another example of a president who changed his image after his presidency. Between leaving office and being awarded the Nobel Peace Prize, Updegrove explained that Carter’s outreach through the Carter Center overshadowed his administration.

Carter really considers the Carter Center as his legacy, not his presidency, Updegrove said.

Updegrove feels that it is up to history to decide what Bush’s legacy will be.

He said that Johnson wanted his library to objectively depict his administration “with the bark off,” and he encouraged this by speeding up the declassification of many Vietnam documents. Updegrove encouraged officials at the Bush Library to do the same.

“I encourage the Bush folks, as much as possible, to give [the Bush administration] an unvarnished look,” Updegrove said. “And let people decide.”