In
The Great Illusion, Angell's primary thesis was, in the words of historian
James Joll, that "the economic cost of war was so great that no one could possibly hope to gain by starting a war the consequences of which would be so disastrous."
[4] For that reason, a general European war was very unlikely to start, and if it did, it would not last long.
[5] He argued that war was economically and socially irrational
[6] and that war between industrial countries was futile because conquest did not pay.
J. D. B. Miller writes: "The 'Great Illusion' was that nations gained by armed confrontation, militarism, war, or conquest."
[7]
According to Angell, the economic interdependence between industrial countries would be "the real guarantor of the good behavior of one state to another",
[6] as it meant that war would be economically harmful to all the countries involved. Moreover, if a conquering power confiscated property in the territory it seized, "the incentive [of the local population] to produce would be sapped and the conquered area be rendered worthless. Thus, the conquering power had to leave property in the hands of the local population while incurring the costs of conquest and occupation."
[7]