Paul McCartney recognizes that John Lennon lived a “really tragic life” and he admires the way his bandmate dealt with it.

The late Beatles star endured a challenging childhood and continued to encounter difficulties in later years, his bandmate and co-songwriter said at the Tribeca Film Festival.

He and Conan O’Brien were discussing photos from McCartney’s new book 1964: Eyes of the Storm. O’Brien selected an image of Lennon seated in the back of a car around the age of 23, saying it carried an air of anxiety and vulnerability. “I don’t know about the anxiety, but the vulnerability is very true,” McCartney replied.

1964: Eyes of the Storm contains nearly 300 pictures taken by McCartney as the Beatles rose to superstardom. He thought he’d lost the trove of shots long ago, before they were rediscovered. “What I love about them is the innocence,” McCartney said. “We didn’t know we were going to get famous. We really wanted to be, but we didn’t know.”

McCartney recently admitted that the Beatles’ first trip to the U.S. led to the realization that they were going to be more than a short-lived success. His Tribeca conversation included more thoughts on their arrival at John F. Kennedy Airport on Feb. 7, 1964: “We were very excited just to be on the plane,” he said. “They got word back to us that there was a big crowd, so we kind of half knew what to expect – but then it was a really big crowd and we were just bowled over. It was nice.

“Immediately after, we did a press conference at the airport,” McCartney added. “We knew that whatever they laid on us, if there was any sort of insult, we knew we could come back with: ‘Well, we are No. 1 in your country!’”

This talk will be released as a future episode of the Conan O’Brien Needs a Friend podcast. McCartney’s book is on sale now. He’s currently working on a documentary about his first post-Beatles decade, to be titled Man on the Run.

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