Rivers of blood

Seven very disillusioned men met in a cafe for a reunion. All were prior members of the elite SAS who had served together. They were appalled at the stupidity, incompetence and deceit of the politicians. They decide to right the wrongs. To emulate the speech of Enoch Powell. However the rivers of blood would be that of the terrorists. Two of the seven were in the police and ideally placed to present targets. Initially targeting drug pushers to acquire a stake. Having only one mandate. Take no prisoners. They bombed the bombers with their own bombs. They became so successful they were incorporated into an international death squad. Their call sign was ROB rivers of blood. That is what they left in their wake.