Robert McNamara's Son Craig Remembers Playing with JFK Jr. and Caroline Kennedy After JFK's Death

Craig McNamara was just 13 years old in November 1963, when his mother drove him to Jackie Kennedy's house to play with young John and Caroline in the days following their father President John F. Kennedy's assassination.

"It was a time dedicated to playfulness and yet with sorrow, just deep, deep sorrow," McNamara, now 73, tells PEOPLE in an interview about his memoir, Because Our Fathers Lied, which published last week.

"I can't imagine the trauma that they were experiencing," he continues. "I felt my role was to bring light and friendship and fun and play, just play mostly, with John."

At the time, John Jr. was just 3 years old and Caroline was 6. McNamara — whose father Robert McNamara served as Secretary of Defense under President Kennedy and then his successor President Lyndon B. Johnson — recalls jumping up and down the stairs with the other children and playing like "kids do". In his memoir, he also remembers with heartbreak that John Jr. loved, even then, to play with model planes. (In 1999, John F. Kennedy, Jr., his wife Carolyn Bessette Kennedy and her sister Lauren Bessette died after the plane he was flying crashed.)

Craig explains that there was "deep friendship" between his parents and the Kennedy family. He remembers Jackie as "a kind and generous and gracious person." After his visits with her children, Jackie even wrote notes to him on her young son's behalf.

"Dear Craig, Thank you for my letter and my helicopter and my card of the mountain — I want to play with you if you come to my house," reads one of the sweet letters written in Jackie's hand that's featured in the book. "Craig, I have time to draw you a picture."

But Craig's memoir is more than a nostalgic look back at the time pre- and post-Camelot. Because Our Fathers Lied is a complex father-son story in which Craig grapples with his dad's role in the much-protested Vietnam War — and Robert's longtime silence.

Following President Kennedy's death, Robert helped Jackie pick out the grave site in Arlington Cemetery. Even in mourning, Jackie took the time to pick out a "memento" for Robert and decided to give him the two chairs from the cabinet room that he and the president used to sit in, Craig explains. "I think every day my father would probably look at those chairs and bring back memories of his friendship and loss," he says. After Robert's death, the chairs were disassembled and made into art by the artist Danh Vo, which was a "release" for Craig, who originally wanted them in his home.

"They serve humanity much better there," Craig says of the chairs being displayed in a public forum. "They tell the story of two dedicated leaders who made disastrous decisions about Vietnam."

The Vietnam War, which began in 1954 and ended in 1975, was a longtime conflict in which the US allied with the government of South Vietnam to combat the communist government of North Vietnam and its allies stationed in the south, the Vietcong. (In 1975, communist forces won South Vietnam and formed the Socialist Republic of Vietnam a year later.) In 1995, Vietnam released an official reporting stating that as many as two million civilians in the war-torn nation and more than one million North Vietnamese and Vietcong soldiers died. The U.S. lost almost 60,000 American soldiers, alongside 200,000-250,000 South Vietnamese soldiers, according to Britannica.

Robert McNamara, as secretary of defense, was one of the main orchestrators of the war and helped spread the lies about the successes of the divisive conflict, until the truth came out when the Pentagon Papers were leaked to The New York Times in 1971. Following the release of the documents, he was scorned and criticized.

During the war, as Robert traveled back and forth to the Johnson White House, he sometimes brought his son Craig along, who looked on.

"I realized that my entire life has been lived through the lens of the Vietnam War and consequently [so is] the relationship with my father," says Craig, who started writing his memoir four years ago.

Craig explains that the loss of so much life and the personal tragedies that continue to play out because of the war "haunt" him. He also continues to struggle with his father's silence and lack of complete apology. (Robert McNamara died at the age of 93 in 2009.)

"My father was very loving to me, no doubt," he says. "We had a strong love for each other, and that makes it even more difficult. How do you reconcile your love for a parent when you realize that they have not been truthful to you on something so important?"

Craig wishes his father would have fully apologized in a public way — and told him the truth when he asked privately about the war. The author also yearned for Robert to listen to the people whose lives were "upended" by the violence.

"Do what you can to positively impact the lives of families who've been affected by Agent Orange," says Craig of the vision he had for his father. "This would've been a reckoning for each of us, I think. For my father and myself."

In Because Our Fathers Lied, Craig recalls joining anti-Vietnam War protests and traveling by motorcycle throughout Central and South America to learn about farming. Since 1980, he's run Sierra Orchards, a walnut farm he owns with his wife Julie in California. Craig did everything he could to distance himself from his father's blood-stained legacy.

While doing research for the book, Craig uncovered an old interview with Life Magazine in which Robert explained why he couldn't write his own memoir and admit to his mistakes earlier than he did. (In the '90s, Robert admitted in his memoir that his conduct was "wrong, terribly wrong," according to The New York Times.) In summation, Robert was focused on "loyalty," his son explains.

"What Robert McNamara is saying there is that his loyalty was to the president, and yet the oath of office that he and the other cabinet members took was to defend the constitution of the United States," says Craig. "So it's something that I can't abide by, that he didn't have a higher loyalty to humanity, for example."

Craig's love for his father is complex, just like Robert's legacy, but it's undeniable. The lessons he hopes readers will take from his memoir are also nuanced.

"The lessons of the Vietnam War are very pertinent today: aggressions based on lies and misinformation lead to prolonged conflicts," he says. "We've seen that throughout history and we've seen it through recent history in Iraq and Afghanistan."

At the very end of his book, Craig recalls reading a Vanity Fair article from 2014 about Jackie Kennedy. Craig learned that his parents had given Jackie two portraits of her late husband to choose from — ones she couldn't accept.

"When Secretary of Defense Bob McNamara and his wife, Marg, sent over two painted portraits of J.F.K. and urged her to accept one as a gift, Jackie realized that though she especially admired the smaller of the pair, which showed her late husband in a seated position, she simply could not bear to keep it," wrote Barbara Leaming in the Vanity Fair article, which Craig cites in his memoir.

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"In anticipation of returning both paintings, she propped them up just outside her bedroom door. One evening in December, young John emerged from Jackie's room," she continued. "Spotting a portrait of his father, he removed a lollipop from his mouth and kissed the image, saying, 'Good night, Daddy.' Jackie related the episode to Marg McNamara by way of explanation as to why it would be impossible to have such a picture near. She said it brought to the surface too many things."

After sharing this anecdote in his memoir, Craig explains that he understands Jackie's decision. He writes that while keeping images and memories of his late father is painful, he cannot "disown" his dad.

"To say that I hate him, to call him evil, to deny the love I have for him — these things would seem, temporarily, to relieve certain pressures," writes Craig in his memoir.

"But they wouldn't be the truth. I don't want that, because I want to be honest. It's impossible not to be my father's son; I can't be what I am. This is not the end for me."

Because Our Fathers Lied is on sale now.