What is the importance of the band, Black Flag, in the memoir, Broken Summers?

Black Flag is the rock band in which Henry Rollins was a lead singer. The band was originally formed with Chuck Dukowski and Greg Ginn, with singers and drummers rotating through. The band is reconstituted by Greg Ginn after Henry Rollins does his Rise Above tour, but the reviews of Ginn's efforts are highly critical, and the mantle of Black Flag's energy and purpose seems to have passed, in Rollins' account, to Rollins and his supporters.