Conservatives fired the first verbal "shots" in this conflict by complaining in 2003 that the video, produced in 1994 with the help of high school students from around the nation, implies that Abraham Lincoln supported abortion, homosexuality and liberal causes.
The marble memorial to Lincoln, the first Republican president, draws more than 4 million visitors a year. Many stop at a first-floor exhibit to see an eight-minute video that showcases Martin Luther King Jr.'s "I Have a Dream" speech, presidential visits and glimpses of dozens of protest marches at the memorial on the National Mall.
Park Service documents, released recently under the Freedom of Information Act to two liberal advocacy groups, show the agency moved quickly to assuage conservatives' ire.
The service bought footage of President Bush, pro-gun demonstrations and pro-Iraq war rallies and even considered cutting out a section showing former President Clinton, a Democrat.
Park Service officials said they wanted the video to be politically balanced but refused to provide a copy of the revision to The Associated Press, saying it was still being evaluated.
Students who worked on and collected money for the project were surprised by the effort to give their display a more conservative touch.
"The Lincoln Memorial is America's soapbox," said Ilene M. Morgan of Los Angeles, who as a Scottsdale, Ariz., high school student helped organize the project. "This was where people have stood to get America's attention. That's what we were trying to capture."
The service has spent about $20,000 revamping the video and buying footage — including some from The Associated Press — after conservative political groups organized a campaign of petitions and e-mails demanding changes.
"The video gave the impression that Lincoln would have supported abortion and homosexuality," said the Web site of Rev. Louis Sheldon's Traditional Values Coalition. It cited footage showing rallies at the memorial by abortion and gay rights supporters and war opponents but no similar footage from Christian and conservative interests.
"Absent from the video were any Promise Keepers marches or Marches for Jesus rallies at the capital. The video was totally skewed to present only a leftist viewpoint," the Web site said. Andrea Lafferty, executive director of Sheldon's group, said Thursday, "The department knows there's a problem and we don't know why they haven't dealt with it in a timely manner."