Jolles himself is a bit obscure to students of military affairs, largely because his translation of On War was his only published effort in that field.
Offered a teaching position at the University of Chicago, he entered the United States with his new British wife in 1938.
These efforts grew out of both patriotism and self-interest: the university's leaders were concerned that unless they established Chicago as a center of military learning and research, the university's considerable assets (particularly in cartography and linguistics) might be hauled off in army trucks, "to be returned torn and soiled, if at all."
His British father-in-law (a retired professor of classics) provided assistance with the English, although he too had little military background and was new to Clausewitz.
His purpose in translating it was to argue that what Clausewitz had to say was much more relevant to the Western Allies than to Germany, and that the Germans' one-sidedly offensive interpretation of On War would prove to be, for them, a fatal error.
This is but one part of his theory and far from the most important one, for he goes on to show why Napoleon, greatest of all aggressors up to that time, was necessarily in the end completely defeated.