New York - New York Mayor Bill de Blasio believes the United States is confronting "centuries of racism," after a week of protests that shook major cities across the country.America's largest city has become the centre point of the demonstrations demanding justice for black men who have died at the hands of white policemen in recent weeks."We have to have an honest conversation in this country about a history of racism, we have to have an honest conversation about the problems that have caused parents to feel that their children may be in danger in their dynamics with police, when in fact police are there to protect them," he told ABC News."Our police keep us safe, and yet there's been not just decades of problems, a history of centuries of racism that undergird this reality."De Blasio, who is white and married to a black woman with whom he has mixed-race children, added: "We have to retrain police forces in how to work with communities differently, we have to work on things like body cameras that will provide a different level of transparency and accountability."This is something systemic and we bluntly have to talk about the historical racial dynamics underlying [it]." Speaking from personal experience, de Blasio told ABC that he feared for his son's safety in dealing with the police."What parents have done for decades with children of colour, especially young men of colour, is train them to be very careful, when they have a connection with a police officer, when they have an encounter with a police officer," he said. "It's different for a white child, it's just a reality in this country. "And with Dante, very early on, my son, we used to say, look, if a police officer stops you, do everything he tells you to do, don't move suddenly, don't reach for your cellphone, because we knew, sadly, there is a greater chance it might be misinterpreted if it was a young man of colour."He continued: "There's that fear that there could be that moment of misunderstanding with a young man of colour, and that young man may never come back."