The friends and enemies William Safire collected during a lifetime in political Washington silently greeted him when he ascended a narrow staircase in his Chevy Chase home and entered his office.

There, on the walls surrounding Safire’s desk, were more than 1,500 books he amassed in Washington working as a speechwriter for President Richard M. Nixon, then as an op-ed writer and language columnist for the New York Times.

Henry Kissinger’s titles were up there. Margaret Thatcher’s. Bob Woodward’s. Even Saul Bellow’s. And, of course, Nixon’s.

Now, a decade after Safire’s death, his books — with gossipy personal inscriptions and intimate letters tucked inside — are up for sale. Capitol Hill Books, the charmingly cramped used book shop near Eastern Market, recently struck a deal with Safire’s estate for the collection.

In bringing Safire’s books to market, the store is revealing — and promoting — an extraordinary, sometimes cagey glimpse into the country’s political and intellectual history, a throwback to the days when political enemies could attend each other’s book parties and politely enjoy deviled eggs.

“That’s really the fun part of this,” said Aaron Beckwith, the store’s co-owner. “You go down the rabbit hole and start to fill in gaps from history and you see some pretty incredible things.”

Like Nixon.

Does his strange behavior ever underwhelm? Not with his tapes. And certainly not, it turns out, with his book inscriptions.

In 1978, the disgraced ex-president published “The Memoirs of Richard Nixon.” Five years earlier, the New York Times reported that Nixon authorized a “national security” wiretap on Safire while he served as a White House speechwriter. Safire then blasted Nixon in a column.

Nixon’s inscription in the copy he sent Safire — sitting on his office shelf for 40 years — spun Beckwith’s head.

“To Bill,” Nixon wrote. “With deep appreciation for his wise counsel over the years and for his service to the nation in government and in the media. Sincerely, Richard M. Nixon.”

When the store began listing the books last month, the Nixon memoirs sold almost immediately, fetching $400, well above other signed copies. So did “Diplomacy,” a history of foreign relations by Kissinger, who served as Nixon’s secretary of state and was a frequent target of Safire in his columns.

Safire had a curious filing system in which he often tucked letters he received from notable people in the books they wrote. A letter inside “Diplomacy,” marking Safire’s retirement from the Times, seems written from another planet when read in the context of today’s grenade-style political combat.

“There were not a few occasions that I was yearning for your last column,” Kissinger wrote. “Now that it has happened, I confess to a case of nostalgia only slightly tinged with exasperation. You performed a great service as a curmudgeonly sentinel on behalf of freedom, and I shall miss your integrity and commitment as a regular diet.”

Not all of the inscriptions and correspondence were that diplomatic, particularly when the authors referenced others.

A letter from contrarian journalist Robert Sherrill stored inside his 1968 book “The Drugstore Liberal” commends Safire for “carving” on John F. Kennedy. “We need to cut that myth down to about the size of a walnut,” Sherrill wrote. “Or a pea.”

Best wishes, of course.

Tucked inside Russell Baker’s 1965 book “All Things Considered” is a 1975 letter from Safire’s New York Times colleague with this assessment of Kissinger: “Ego doth make him a s--t.” The book — and the letter — are still available. The price: $70.

Safire’s collection, which also includes dozens of centuries-old language tomes he often used in writing his popular language column, enters the used and rare book market with print works on the ascendance after years of decline.

Independent bookstores are thriving. Hardcover book sales are trending up. For collectors, books owned and written in by notable people have become highly coveted.

“It’s no longer just an ordinary copy of the book,” said Rob Rulon-Miller, a rare books dealer in Minnesota who sold Safire language books and appraised his collection. “It’s Safire’s copy of the book.”

Though Capitol Hill Books declined to say how much it paid for Safire’s books, Rulon-Miller said his appraisal, back during George H.W. Bush’s presidency, was in “the tens of thousands” of dollars.

Safire’s home office was, to him, a library. Books lined much of the room. They were loosely organized. In one area, books on language. In another, signed books by political and cultural figures, many with typed and handwritten letters inside.

In addition to political intrigue, Safire’s collection has revealed a friendly and intellectually curious correspondence with a range of cultural elites.

Safire seemed particularly close with Nobel laureate Saul Bellow, who died in 2005. Capitol Hill Books is selling several Bellow works containing copies of letters and notes he sent Safire.

In 1995, after Safire’s novel “Sleeper Spy” received an unfriendly review in the Times, Bellow tried to cheer him up.

“My naivete is so persistent that I was surprised,” Bellow wrote, “by the offensive review of your novel in the daily Times. I thought your book was ingenious, diverting and even instructive.”

Herman Wouk wrote with praise. So did David Mamet — about Israel.

“Please permit an American Jew to offer his appreciation of your strong support of Israel,” Mamet wrote by hand. “With all respect, David Mamet."

The wonders go on.

After Safire wrote a column about the word do-rag, Colin Powell sent him an actual do-rag, which Safire stored inside Powell’s book “My American Journey.” It sold for $125.

Alan Dershowitz, in a book on Thomas Jefferson, scribbled, “To Bill, Who even Jefferson could learn from!”

Novelist Joyce Carol Oates inscribed a book “with much admiration for your writing, and wit; and very best wishes.” Kurt Vonnegut signed “Jailbird” with this: “Most respectfully for the writer William Safire.”

But with Safire, it’s the political books that most intrigue.

He won the Pulitzer Prize for commentary in 1978 for columns about a scandal during the Carter administration involving T. Bertram Lance, director of the Office of Management and Budget.

Inside a multivolume government-published book titled “Matters Relating to T. Bertram Lance: Hearings Before the Committee on Governmental Affairs, United States Senate,” was a letter from — of all people — Lance.

“Dear William,” it said. “The Bible says ‘Love those who despise you.’ May you and yours have a Merry Christmas & a Happy new year — Bert Lance.”

It’s still available — for $100.

“To Bill Safire,” Woodward scribbled. “Watergate is still alive.”

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