Why does bono choose not to have any children and how does he feel about that choice?

Bono chose not to have children because of what he called his father's 'walking blues.' During reconstruction, many freed blacks (we assume Bono's father was once a slave) had nowhere to live, no work, and no stability. Bono didn't want to have children because he didn't want to repreat his father's mistakes. In answer to the second part of your question, I believe Bono regretted his decision.