College Park, Md. ? Sometime in the very near future, Bill Cowell will hunker down in front of a bulky 25-year-old tape player in a nondescript cubicle here at the National Archives, clap on a headset and, guided by codes on a sheet of paper, find a precise spot on a thin, brown ribbon to mark with his grease pencil.

Then Cowell will flip a couple of levers, slip the magnetic tape into a small aluminum block and slice away the voice of former President Nixon.

Cowell, 59, can’t tell you what words he’ll be cutting. A former military intelligence officer, Cowell was hired as a kind of historical surgeon at the National Archives because he knows how to keep a secret.

But he will say that the conversations involve mundane moments in Nixon family life and the late president’s comments on internal Republican Party politics — details that would be fascinating for biographers but that a federal judge ruled 11 years ago were none of the nation’s business.

So Cowell will cut. Uncomfortably, and with a nagging sense that he’s destroying something of value.

“These tapes were recorded in the Nixon White House by Nixon, for Nixon, and should be a national treasure, and here we are cutting them up,” said Cowell — who, despite his intelligence background, has an archivist’s passion for publicly preserving the past. “Obviously, I don’t think too highly of the court decision, but we’re kind of stuck with it. I really do think we’re destroying a historical artifact that should be preserved.”

Cowell and others at the National Archives are editing Nixon’s tapes for public release — the final stage of a legal wrestling match that began in 1974 when Congress, fearful that Nixon would destroy evidence in the days after his resignation, ordered that the 37th president’s White House records be seized.

That included the infamous White House tapes: some 2,800 hours of conversations surreptitiously recorded on 950 reels via microphones hidden in the White House, the Old Executive Office Building and in three places at Camp David.

All the machines were voice-activated, which meant they captured virtually everything that was said: Small talk. Political strategy. Arms negotiations. The Watergate cover-up. Family matters. To listen is to be a fly on the Oval Office wall, as though “The West Wing” were a reality radio show.

“That is really the stuff of history,” said Roger Morris, a former National Security Council staff member under Nixon and President Lyndon B. Johnson whose books include a Nixon biography. Morris said he was dismayed by the work the National Archives finds itself forced to do: “I just have a kind of blanket and sweeping preference for opening up everything.”

Nixon, though, felt otherwise.

After Congress seized the files, Nixon argued in court that Congress lacked the authority to take his property. He lost that argument but did persuade the court that details about his family and internal Republican Party conversations were not matters of legitimate public interest. Those are the words Cowell and his colleagues slowly are excising.