Washington (AFP) – President Joe Biden will mark the second anniversary of the murder of George Floyd on Wednesday, the day after a school shooting that came as a cruel reminder of his powerlessness to rein in America’s demons. It was to be a ceremony symbolizing reconciliation, in one of the White House’s state rooms, with families of victims of police violence alongside representatives of the police. But the school massacre in Uvale, Texas, in which 19 schoolchildren and two teachers died, will be on everyone’s mind when Biden signs a decree described as historic by his administration, aimed…