War of aggression
The International Military Tribunal at Nuremberg held following World War II that the waging of a war of aggression is:
essentially an evil thing…to initiate a war of aggression…is not only an international crime; it is the supreme international crime, differing only from other war crimes in that it contains within itself the accumulated evil of the whole.[58]
http://www.un.org/en/sections/un-charter/chapter-vii/index.html
https://en.wikipedia.org/wiki/List_of_wars_involving_Poland
https://pov-tc.pbs.org/pov/downloads/2016/pov-ofmenandwar-lesson-plan.pdf
