Article 6 of the Charter of the International Military Tribunal at Nuremberg:
ARTICLE 6
The Tribunal established by the Agreement referred to in Article 1 hereof for the trial and punishment of the major war criminals of the European Axis countries shall have the power to try and punish persons who, acting in the interests of the European Axis countries, whether as individuals or as members of organizations, committed any of the following crimes.
The following acts, or any of them, are crimes coming within the jurisdiction of the Tribunal for which there shall be individual responsibility:
(a) Crimes against Peace: namely, planning, preparation, initiation or waging of a war of aggression, or a war in violation of international treaties, agreements or assurances, or participation in a Common Plan or Conspiracy for the accomplishment of any of the foregoing; (b) War Crimes: namely, violations of the laws or customs of war. Such violations shall include, but not be limited to, murder, ill-treatment or deportation to slave labor or for any other purpose of civilian population of or in occupied territory, murder or ill-treatment of prisoners of war or persons on the seas, killing of hostages, plunder of public or private property, wanton destruction of cities, towns, or villages, or devastation not justified by military necessity;
(c) Crimes against Humanity: namely, murder, extermination, enslavement, deportation, and other inhumane acts committed against any civilian population, before or during the war,14 or persecutions on political, racial, or religious grounds in execution of or in connection with any crime within the jurisdiction of the Tribunal, whether or not in violation of domestic law of the country where perpetrated.
Leaders, organizers, instigators, and accomplices participating in the formulation or execution
of a Common Plan or Conspiracy to commit any of the foregoing crimes are responsible for all acts performed by any persons in execution of such plan.
You don't need to be a lawyer to understand this principle; a war of aggression is unlawful under International Law. You only need the ability to read. What I can't fthom is that an otherwise rational person like you would want to continue to defend the indefensible. Blair did not blunder into this conflict, he helped create it, quite deliberately.