Wiliamson was probably emotionally detached from, and at the same time committed to, the path he had chosen/been recruited to. In much the same way that people like McBride (and others - think Church Square) carried out murder against innocent people so Williamson operated against his perceived enemy. His was to engage people win their confidence and then act against them whereas the other side crept up on people and killed them. If those responsible for the deaths of nightclub patrons and city pedestrians are now left alone.....
Those to whom the victory is awarded get to write the history and make the requisite noises. Those relegated to the failed side fade away and quietly get on with their lives if that is allowed them. It benefits no-one to keep scratching the wounds on either side - in fact it inflames things all over again. Perhaps the book ought not to have been written.