On November 21, 1945, in his opening statement before the International Military Tribunal at Nuremberg, Robert Jackson stated the U.S. position on aggression as follows:

[A]n "aggressor" is generally held to be that state which is the first to commit any of the following actions: (1) Declaration of war upon another State; (2) Invasion by its armed forces, with or without a declaration war, of the territory of another State; (3) Attack by its land, naval, or air forces, with or without a declaration of war, on the territory, vessels, or aircraft of another State;(4) Provision of support to armed bands formed in the territory of another State, or refusal, notwithstanding the request of the invaded State, to take in its own territory, all the measures in its power to deprive those bands of all assistance or protection.

He added,

[I]t is the general view that no political, military, economic or other considerations shall serve as an excuse or justification for such actions; but exercise of the right of legitimate self-defense, that is to say, resistance to an act of aggression, or action to assist a State which has been subjected to aggression, shall not constitute a war of aggression.

      Aggression in the context of war refers to the use of armed force by one state against another state without justification or provocation. It is a violation of international law and can lead to significant political and social consequences. Military aggression is arguably the most serious of all crimes. It a crime against the peace and security of humanity.

      The U.N. General Assembly's resolution of December 14, 1974, defining aggression was a landmark achievement in international law. What it did was establish a clear and concise definition of aggression.

      U.N. Res. 3314 (XXIX) acknowledged that the use of force was only permissible in self-defense or when authorized by the Security Council under Chapter VII of the U.N. Charter and established that aggression was a crime against international peace and security. Further, it encouraged States to cooperate in preventing and suppressing acts of aggression.

      This resolution of the General Assembly was adopted by a vote of 104-0, with 11 abstentions, and has since been widely accepted as the authoritative definition of aggression. It has been used to guide the U.N.'s efforts to prevent and respond to acts of aggression around the world. Indeed, the UN-backed Independent International Commission of Inquiry on Ukraine released a report on March 16, 2023, specifically referencing the proviso.

      Let's consider, now, that self-defense is the only just cause for war that is formally recognized in modern international law. 

   The first questions asked when states go to war are also the easiest to answer: who started the shooting? who sent troops across the border? These are questions of fact, not of judgment, and if the answers are disputed, it is only because of the lies that governments tell. The lies don't, in any case, detain us long; the truth comes out soon enough. Governments lie so as to absolve themselves of the charge of aggression.

Michael Walzer, Just and Unjust Wars (4th ed., 2006), p. 74. 

      So it is that governments pretend to act out of necessity, why they pretend to have just cause, etc., and are only waging war against another land as a last resort. They do so because human experience tells us quite clearly that wars are abominable and do horrific short-term and long-term economic, physical, and mental damage. Therefore, people who thrust nations into war for greedy, selfish, nonsensical, political, or military reasons other than absolute necessity try to avoid condemnation by claiming to act in "self-defense."

      Note that the Bush Administration made certain claims before the U.S. invasion of Iraq designed to make it appear that the attack was a preemptive attack, as opposed to a preventive attack. (Here, those are words of art. That is, they mean something other than what they ordinarily do.)

      Here is why this is important.

      A preemptive war is one initiated by a party when there is a clear and present danger of an imminent attack. It is legal and recognized under both customary and positive international law as a legitimate form of anticipatory self-defense. States have the inherent right to defend themselves in this manner, and it is not deemed an act of aggression. Aggression is always a crime.

      A preventive war, on the other hand, is one wherein a state makes an attack against another state when there is no apparent threat of imminent attack but, rather, is initiated allegedly due to some perceived potential threat in the future. A preventive attack is indistinguishable from aggression and is a crime. A nation cannot, lawfully, simply say that it feels that in a year or two (or five or ten) another nation might or will be a threat and therefore initiate an armed attack. 

      It appears that people inside and outside the Bush Administration pushed one view of the invasion over another to avoid accountability in the form of criminal culpability.
 
      My next essay will treat Judaism, Christianity, Islam, and war. Look for it here on Tuesday, April 4th.