Occasional New York Times columnist Bono offers his thoughts on the extraordinary report about the killings of civil rights demonstrators in Northern Ireland in 1972. A few of the Catholic-side leaders during the long and brutal “troubles” in that place stopped in Lowell over the years, in particular, Gerry Adams and Martin McGuinness. At the Innovative City Conference this week the delegation from Belfast spoke about the suffering endured by people of their city during that time and the way the chaos affected their way of life. Belfast today is rebounding, but has a long way toward renewal. And the violence is not over. Not long ago another policeman there lost both his legs in a horrible incident.