Paul McCartney said he tried to write a song about the recent Ferguson and New York City protests but scrapped it when he felt it wasn't going anywhere. But, he told the Associated Press, he isn't finished with the song yet.

"I was thinking recently about all these protests in New York and around the country," he said. "I thought it would be great to put something down about that, just to add my voice to the thousands of people walking in the streets. I thought it through, and it just didn't come easily. I'm not giving up on it, but it didn't come easily, whereas some other emotions might come easily to me."

While John Lennon was always considered the more politically active Beatle, McCartney has supported his share of causes over the years, particularly ones having to do with animal rights and vegetarianism. He also penned a letter of support for Russian punk rockers Pussy Riot after they were jailed for protesting President Vladimir Putin at a Moscow cathedral. And, as the Associated Press story points out, 'Blackbird' (from the White Album) was written for the Civil Rights movement in 1968.

McCartney also reflected on his past, particularly his Liverpool roots, noting that he and Beatles producer George Martin often get together, and he still has memories of his old songwriting partner when he's composing these days. "I imagine myself back into a room with John, and I'll think, 'Ugh, that's no good,'" he said. "And I'll imagine him saying, 'No, can't do that.' So I'm using him as a sort of judge of what I'm doing."

He apparently checks out Beatles tribute bands once in a while too. McCartney concluded the interview by ruminating on the power of music to spread across the world. "In Japan, these guys were breaking down Queen songs, and the others Beatles songs," he recalled. "They were replicating them amazingly. ... They may not even speak the language that well, but they speak these songs beautifully. I should know that we've had that effect, because it's historically true. But it doesn't always come home to you in quite the way it did that night. I was welling up, and I was (thinking), 'I can't well up to a Queen tribute band.'"

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