Bono has cheered the release of Myanmar's Aung San Suu Kyi who has been detained for two decades under house arrest.
Suu Kyi has won the Nobel Prize in the past in 1991 for her pro democracy stance in a country which is ruled by a military junta.
In a CNN interview, Bono said he was "feeling great" for Suu Kyi.
"It's sort of a cautious joy, because though she's out in the world, ... she's perhaps more vulnerable,I'm very excited, very thrilled at the possibility that this might be the beginning of some sort of rational discussion."
"She is kind of the Mandela of our moment," said Bono, referring to Nelson Mandela,. "She's a character of great grace. Her struggle has become a symbol of what's best about our humanity and worst."
The band composed its hit 2001 single "Walk On" about the 1991 Nobel Peace Prize winner.
"Suu Kyi, with an idea too big for any jail and a spirit too strong for any army, changes our view -- as only real heroes can -- of what we believe is possible," he wrote back then.
He warned however, her release must be permanent.
"For this to be real, there has to be progress toward real peace," said Bono.