In this chapter I will examine the fascinating cases of those civilian leaders of companies that played such a large role in the war effort in Nazi Germany: the Krupp works and the I. G. Farben works. I will use these cases as a lens through which I examine the mens rea element of the crime of aggression. And I will be especially interested in how to characterize the idea of planning to wage a war of aggression. Both Krupp and I. G. Farben were weapons manufacturers who may have lobbied for the war but who were not directly involved in its planning. We will have reason to wonder about the idea of complicity in the crime of aggression. In this respect, the opinion of Judge Paul M. Hebert will be crucial for establishing a possible Nuremberg “precedent” in this domain.

In a war of aggression it is often true that all aspects of the society contributed to the war effort. The question before us is whether civilian leaders of major companies that supplied armaments and vital economic products to the Army and Navy are to be seen as complicit in the waging of aggressive war. In one sense, this is clear-cut – as a matter of causation, the war effort, at least at the scale conducted by Nazi Germany, could not have been undertaken without major industrial help.