Billie Joe Armstrong's songwriting has become more "thoughtful" over time.

The 51-year-old star - who is the lead singer of Green Day - believes that his approach to songwriting has evolved during the course of his career.

During an appearance on the 'Q with Tom Power' podcast, he explained: "It's easy to sing songs when you're younger ... songs like, you know, smash the state. I'm like, 'Yeah, I believe that'. [But] do I believe the 50-year-old man who says smash the state?

"I think when you get older, the world becomes a lot more complex and nuanced in what's going on.

"As time goes on, your ... your views change."

Billie Joe explained that he's particularly careful with his lyrics when he's writing "topical and political" songs.

He shared: "It's taking everything line by line, especially when you're writing stuff that's topical and political. I want it to come from the heart just as much as a love song."

Asked to elaborate, Billie Joe replied: "You want it to be smart and thoughtful."

Meanwhile, Billie Joe previously admitted that he doesn't want to write too many political songs.

The singer fears that he would "take the heart out of it" by saturating the market with political music.

He told 102.1 The Edge: "[With] political songs, it takes a lot of heart to do that, and I think if you keep doing it for the sake of doing it just because you’re angry, then you take the heart out of it. Then it just becomes part of what everyone is complaining about."