In the twentieth century, Geoffrey Robertson said in his book Crimes against Humanity, international law became accepted in the international community.¹ The twenty-first century, he suggested, will be the century of its enforcement. Among the political and judicial advocates who fight for the development of international law, many are driven by a passion to ensure that respect for national sovereignty should not prevent the prosecution of political and military leaders who are guilty of war crimes or of crimes against humanity, especially genocide.