he Great Illusion is a book by Norman Angell, first published in the United Kingdom in 1909 under the title Europe's Optical Illusion and republished in 1910 and subsequently in various enlarged and revised editions under the title The Great Illusion. It is an influential book in the field of international relations. 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." For that reason, a general European war was very unlikely to start, and if it did, it would not last long. He argued that war was economically and socially irrational 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."