SPRINGFIELD, Ill. ? Opening the Abraham Lincoln library and museum, President Bush said Tuesday that its mix of showmanship and scholarship should help generations rediscover the 16th president whose commitment to freedom for all embodies “the meaning and promise of America.”

“From the lunch counter to the schoolhouse door to the Army barracks, President Lincoln has continued to hold this nation to its promises,” Bush told an audience of thousands — including scores of Lincoln impersonators — gathered on a hot day before the low-slung, $145 million complex of wheat-colored stone. “And we will never relent, we will never rest until those promises are met.”

The dedication of the museum portion of the state-of-the-art showplace capped 25 years of effort. The $145 million Abraham Lincoln Presidential Library and Museum, with 40,000 square feet of understated architecture, is designed to generate new interest in Lincoln and explain his life and legacy. The library portion opened last October.

Before the public ceremony, Bush and House Speaker Dennis Hastert, R-Ill., took a 20-minute private tour. With their wives, they were led through a section devoted to Lincoln’s life before his presidency and one on his White House years, as well as an exhibit marking the 140th anniversary of Lincoln’s assassination.

The new library also offers details of the controversies surrounding Lincoln’s policies. The museum presents his changing views on slavery, restrictions on free speech and the limitations of his Emancipation Proclamation.

Sen. Barack Obama, the Illinois Democrat who is the Senate’s only black member, touched gingerly on the questions about Lincoln.

“Lincoln was not a perfect man, nor a perfect president,” Obama said. “By modern standards, his condemnation of slavery might be considered tentative, his Emancipation Proclamation more a military document than a clarion call for justice. He wasn’t immune to political considerations. His temperament could be indecisive and morose.”

Some fear the museum is more about amusement than education, using gimmickry and special effects to bring Lincoln to life.

Abraham Lincoln look-a-likes wait for the start of the dedication ceremonies for the Abraham Lincoln Presidential Library and Museum in Springfield, Ill. Thousands of spectators turned out for Tuesday's dedication of the museum.

Seats shake and cannons belch smoke during a movie. Holographic “ghosts” haunt a presentation on the library’s research. Fake campaign commercials illustrate Lincoln’s political career.

In the library half, which holds the world’s largest collection of Lincoln artifacts and documents, visitors can see a signed copy of the Emancipation Proclamation and a handwritten version of the Gettysburg Address.

But unlike most presidential libraries, this one isn’t operated by the National Archives and it isn’t the official repository of documents from Lincoln’s presidency. The state runs the library and museum, and the federal government has agreed to provide up to $50 million.