Clinton, mother Jennie, sister Janice, father Chris, Christmas 1942. Clint Hill personal collection.

Agents Frank Bales and Clint Hill stand post as President Eisenhower exits a Gettysburg church with a member of the clergy. 1959. Dwight D. Eisenhower Presidential Library

President Eisenhower enjoying a golf outing with Arnold Palmer. AP Photo/Paul Vathis

Huge crowds greet President Eisenhower in Karachi, Pakistan, as he rides with President Ayub Khan in the slow-moving presidential horse-drawn carriage. Dec. 1959. AP Photo

Crowds were so thick upon our evening arrival in New Delhi, India, that at times Prime Minister Nehru exited the car and beat the crowds with a swagger stick. Dec. 1959. AP Photo

SAIC Jim Rowley scans the surging crowd as President Eisenhower waves from the open-top car in New Delhi, India. Dec. 1959. Getty/SLADE Paul

President Eisenhower with controversial dictator Generalissimo Franco in Secret Service car 4-B. Madrid, Spain. Dec. 1959. Dwight D. Eisenhower Presidential Library

President Eisenhower, Press Secretary Jim Hagerty, Mrs. Eisenhower, and me in Newport, Rhode Island. Dwight D. Eisenhower Presidential Library/Jerry Taylor

President Eisenhower with his hand on SAIC Jim Rowley’s shoulder as the crowd engulfs the motorcade in Manila, Philippines. Jerry Behn (left) and other agents form a barrier. AP Photo

President Eisenhower rides in the back of an open convertible in San Diego as I work the motorcade route. Clint Hill personal collection

President Eisenhower and Vice President Nixon—then a presidential candidate—ride together in an open-top car through the streets of Manhattan during the 1960 campaign. AP Photo

I keep a watchful eye on the press as President Kennedy meets with Secretary of State Dean Rusk in Palm Beach. April 1961. AP Photo

Nicole Alphand (wife of the French ambassador) interprets for Mrs. de Gaulle and President Kennedy as Mrs. Kennedy charms President de Gaulle using her fluency in French during the trip to Paris. 1961. John F. Kennedy Presidential Library & Museum/Boston

Crowds and the press swarm around President and Mrs. Kennedy in Hyannis Port with me (behind photographer), and agents Bill Payne and John Campion. Aug. 1961. AP Photo

Keeping a watchful eye as President and Mrs. Kennedy exit St. Francis Xavier Church in Hyannis Port. John F. Kennedy Presidential Library & Museum/Boston

President Kennedy sought advice from former President Eisenhower at Camp David after the Bay of Pigs fiasco in April 1961. John F. Kennedy Presidential Library & Museum/Boston

President Kennedy signed this photo after learning I was injured while helping him and Chuck Spalding out of the rocks on the sailboat Victura. July 1962. Clint Hill personal collection

I had difficulty breathing at Mexico City’s high elevation as I jogged alongside SS-100-X. July 1, 1962. John F. Kennedy Presidential Library & Museum/Boston

Massive amounts of confetti created a security nightmare as President Kennedy rode with President Adolfo López of Mexico through Mexico City. Two million people lined the motorcade route. June 30, 1962. John F. Kennedy Presidential Library & Museum/Boston

President Kennedy jokingly chides me for allowing his friends to rest during the 50-mile hike. Standing left to right: Corpsman Tom Mills, JFK, Dr. Max Jacobson, and me. Chuck Spalding and Prince Radziwill on ground. © 2011 Mark Shaw/mptvimages.com

JFK presents me with a paper medal, “To Dazzle,” after the 50-mile hike. Behind left to right: Lee Radziwill, Dr. Jacobson, other friends, and Prince Radziwill. Clint Hill personal collection

We often wore tuxedos to blend in. Agent Jim Johnson, Mrs. Kennedy, JFK, and me, leaving a formal event. John F. Kennedy Presidential Library & Museum/Boston

My favorite photo of President John F. Kennedy. Happy at the helm of Manitou. 1962. John F. Kennedy Presidential Library & Museum/Boston

Surprise party for President Kennedy in the White House Navy Mess on his 46th birthday. JFK, Muggsy O’Leary, me, Mrs. Kennedy, Nancy Tuckerman, and other staff members. John F. Kennedy Presidential Library & Museum/Boston

President Kennedy opening birthday presents aboard the USS Sequoia. Left to right: the back of Lem Billings, Ethel Kennedy, JFK, Paul “Red” Fay, Mrs. Kennedy, and Mrs. David Niven. John F. Kennedy Presidential Library & Museum/Boston

President Kennedy rode in open-top cars throughout Europe, attracting massive crowds wherever he went, with only a handful of agents available to protect him. Cork, Ireland. John F. Kennedy Presidential Library & Museum/Boston

President Kennedy treasured time with his children. Here with Caroline, summer 1963. John F. Kennedy Presidential Library & Museum/Boston

I keep an eye on the press as President Kennedy, Caroline, and John exit the Otis AFB hospital after visiting Mrs. Kennedy two days after the death of baby Patrick. Aug 11, 1963. US Air Force Photo

President Kennedy enjoying time with his children his last weekend at Atoka. Nov. 10, 1963. John F. Kennedy Presidential Library & Museum/Boston

JFK squirms with laughter as a pony nuzzles him, with Tony Bradlee at Atoka. Nov. 10, 1963. John F. Kennedy Presidential Library & Museum/Boston

President Kennedy laughs with John as they enter Arlington National Cemetery Nov. 11, 1963. Generals Ted Clifton and Godfrey McHugh (rear). AP Photo

President and Mrs. Kennedy prepare to depart Carswell Air Force Base for Love Field, Dallas. Me in sunglasses, Agent Ned Hall on right. Nov. 22, 1963. University of Texas at Arlington Library Special Collections

Turning onto Main St., Dallas, I crouched on the rear bumper to be closer to Mrs. Kennedy. Agents Jack Ready and Paul Landis scan the crowds from the follow-up car. Darrell Heikes, photographer, Dallas Times Herald Collection/The Sixth Floor Museum at Dealey Plaza.

Expecting more shots were coming, I wedged myself up on the rear seat to protect the stricken president, Governor Connally, and their wives as we raced to Parkland Hospital. AP Photo

Trying to control my emotions as former Presidents Truman and Eisenhower pay condolences to Mrs. Kennedy (in car) outside St. Matthew’s Cathedral with the flag-draped coffin in the foreground. Margaret Truman, Ted Kennedy, and Robert Kennedy also in photo. John F. Kennedy Presidential Library & Museum/Boston

Escorting Mrs. Kennedy with John, Caroline, and Robert Kennedy to visit JFK’s burial site on what would have been his 47th birthday. May 29, 1964. Lee Lockwood/Getty/LIFE Images Collection

President Johnson bids goodbye to Jacqueline Kennedy (with Robert Kennedy) at her 1040 Fifth Avenue residence as I look on. Oct. 1964. LBJ Library photo

I was standing just behind Agent Roy Kellerman in the doorway as Lyndon Johnson took the oath of office on Air Force One with Mrs. Kennedy by his side. It was surreal—and crushingly sad. John F. Kennedy Presidential Library & Museum/Boston

Flight crews run for their aircraft at the LBJ Ranch after notification that President Johnson wants to fly somewhere without prior notice. A typical occurrence. LBJ Library photo by Yoichi Okamoto

President Johnson discusses Vietnam situation with Joint Chiefs of Staff around picnic table on front lawn of LBJ Ranch. Clockwise from LBJ: Sec. of Defense Robert McNamara, a military assistant, Gen. Curtis LeMay, Gen. Earle Wheeler, Deputy Sec. of Defense Cyrus Vance, Gen. Harold Johnson, Adm. David McDonald, and Gen. Wallace Greene. Dec. 22, 1964. LBJ Library photo by Yoichi Okamoto

I walked alongside the left rear of presidential limousine SS-100-X—the same car in which JFK was assassinated—in Johnson’s 1965 Inaugural Parade. LBJ Library photo

In a secret meeting at Andrews Air Force Base, President Johnson conferred privately with former President Eisenhower on board a Jetstar aircraft. Oct. 5, 1965. LBJ Library photo by Yoichi Okamoto

LBJ stands out of the Mexican presidential limousine with President Díaz Ordaz as agents try to control the surging crowds in Mexico City, April 1966. I’m making a request of a Mexican official immediately in front of the car. LBJ Library photo by Yoichi Okamoto

Making preparations for a presidential movement in Honolulu. Left to right: Lem Johns, me on the radio, Dick Johnsen, and an unidentified agent. May 1966. LBJ Library photo by Yoichi Okamoto

A light moment on Air Force One. Left to right: LBJ, Sgt. Robert Duffey, me, Agent Bob Taylor, and SAIC Lem Johns (foreground). LBJ Library photo by Yoichi Okamoto

As LBJ climbs out of the car into the overwhelming crowd in Honolulu, I stand in the follow-up car, scanning the scene and obviously upset by the president’s risk-taking. Oct. 17, 1966. LBJ Library photo by Frank Wolfe

Protestors in Melbourne, Australia, throw paint at the president’s car. Agents Lem Johns, Dick Johnsen, and Rufus Youngblood bear the brunt of the attack. Oct. 1966. AP Photo

It was a special occasion for the senior agents on the White House Detail and our wives to be invited guests for dinner at the LBJ Ranch. Dick Johnsen, myself, Peggy Youngblood, LBJ, Rufus Youngblood, and Betty Godfrey in foreground. LBJ Library photo by Yoichi Okamoto

Gwen and I pose with President and Mrs. Johnson at the LBJ Ranch. Dec. 1966. LBJ Library photo by Yoichi Okamoto

Rev. Billy Graham and President Johnson greet an enthusiastic crowd at the White House, as I remain close. June 14, 1967. LBJ Library photo by Kevin Smith

Russia’s Premier Aleksei Kosygin and President Johnson (Russian interpreter between them) meet at a quickly arranged summit at the home of Glassboro College’s president. Soviet Ambassador Dobrynin on right. June 23, 1967. LBJ Library photo by Yoichi Okamoto

I stand on the rear of the jeep as President Johnson and General Westmoreland inspect the troops during a surprise visit to Cam Ranh Bay, Vietnam. Dec. 23, 1967. LBJ Library photo by Yoichi Okamoto

I remain close to President Johnson as he shakes hands with the soldiers at Cam Ranh Bay, Vietnam. Dec. 23, 1967. LBJ Library photo by Frank Wolfe

I accompanied LBJ to retirement ceremony for Sec. of Defense McNamara at the Pentagon—a day when almost everything went wrong. Feb. 29, 1968. Clint Hill personal collection

President Johnson admonishing me for something as we disembark Marine One on the South Lawn. LBJ Library photo by Yoichi Okamoto

President Johnson on phone receiving information on the assassination of Martin Luther King Jr. as members of the staff watch news reports on three TVs in the Oval Office. LBJ Library photo by Mike Geissinger

Robert F. Kennedy’s burial at Arlington National Cemetery. Left to right: Ethel and Ted Kennedy; foreground: President Johnson; Deputy Director Rufus Youngblood and me. June 8, 1968. Getty/Michael Ochs Archives

President Johnson hosts Republican presidential candidate Richard Nixon and his staff for a briefing at the LBJ Ranch. Left to right: Spiro Agnew, CIA Director Dick Helms, Ron Ziegler, Nixon, President Johnson, Cyrus Vance, Bob Haldeman, Jim Jones, Tom Johnson, and Dean Rusk. Aug. 10, 1968. LBJ Library photo by Yoichi Okamoto

It was embarrassing modeling the custom-made ranch clothes LBJ gifted me. The president and secretary Marie Fehmer comment from the pool as Ken Gaddis laughs. Aug. 10, 1968. LBJ Library photo by Yoichi Okamoto

Meeting comedian Jack Benny with White House press aide Tom Johnson standing in the background. May 1968. LBJ Library photo by Yoichi Okamoto

Judy Agnew, President Johnson, incoming Vice President Agnew, and Mrs. Johnson at the White House on Inauguration Day 1969. I’m standing lower right by the car. AP Photo

I was riding in the right front seat of SS-100-X, as the other agents reacted to anti-Nixon demonstrators hurling rocks and other debris during the 1969 Inaugural Parade. Richard M. Nixon Library

I stood behind Vice President Agnew and his wife, and former President and Mrs. Johnson observing the launch of the Apollo 11 moon shot at Cape Kennedy. July 16, 1969 Clint Hill personal collection/NASA

The press had a field day with President Nixon’s uniform design for the White House police division of the Secret Service. I thought they were ridiculous. U.S. Secret Service Photo

Agents Chuck Zboril and Don Gautreau scan the crowd as President Nixon stands out of the roof amid swarming crowds in Manila, Philippines. AP Photo

Vice President Agnew visiting my mother, Jennie Hill, in Minot, North Dakota. My cousin Olga’s husband, Paul Froeming, is in the background. Clint Hill personal collection

Secret Service agents Ham Brown (rear) and Gary Jenkins with President Nixon during his predawn excursion to the Lincoln Memorial to talk to antiwar protesters. AP Photo

We ringed the White House complex with buses as hundreds of thousands of antiwar protesters amassed in Washington, DC, in May 1970. AP Photo

Secret Service agents Bill Duncan and Bob Taylor try to ensure President Nixon’s security when he gets on top of the car in Berlin, Germany, just weeks after taking office in 1969. AP Photo

The day Elvis Presley showed up—unannounced—at the White House with a letter to President Nixon offering his services as a “Federal Agent at large.” Nixon Presidential Library & Museum

I was very pleased when we finally allowed women to become agents in December 1971. Director James J. Rowley with the first five: Holly Hufschmidt, Laurie Anderson, Phyllis Shantz, Sue Ann Baker, and Kathryn Clark. U.S. Secret Service Photo

Vice President Spiro Agnew exits the Baltimore Courthouse flanked by Secret Service agents Jerry Parr and Jimmy Taylor after admitting guilt to tax evasion charges, and announcing his resignation as Vice President. Oct. 10, 1973. Bettman/Corbis

I was in the East Room of the White House to witness the swearing-in of Gerald R. Ford as the 38th President of the United States. Finally “our long national nightmare” was over. Aug. 9, 1974. Courtesy Gerald R. Ford Presidential Library

I was among the many members of the White House staff who watched as President and Mrs. Nixon departed the White House for the last time. Nixon daughters Julie and Tricia with their husbands in the background. Nixon Presidential Library & Museum

Helping to clear a passageway for President Ford to exit a speech site in Chicago when I was assistant director. Courtesy Gerald R. Ford Presidential Library

President Ford visits Secret Service headquarters shortly after taking office. (Left to right) myself, Dep. Dir. Pat Boggs, President Ford, Asst. Dir. Burrill Peterson, and Agent Bob Snow. U.S. Secret Service Photo