Blair ,mandela and the pope are they above the law?

how come they cant at least be tried for crimes committed , asil nadir is theres still a warrant for lord lucan , from a international law view , they should be at least arrested , blair for murder of iraqis , the pope for conspiracy to ist known paedophiles and mandela , for conspiracy with charles taylor , blood diamonds , mandela knows whats going on in africa he must have known who taylor was