The international instability that prevailed after 1918 was more directly responsible for the second World War than it was for the collapse of the League. It was not the sole cause of that war, however, and Mr A. J. P. Taylor's book on the origins of the war of 1939 is important because it recognises this. It is an unsatisfactory book because it places the various causes of the war in a wrong relationship; but it provides a better basis than most other accounts for a discussion of how that relationship ought to be studied.

‘Wars’, Mr Taylor writes, ‘are much like road accidents. They have a general cause and particular causes at the same time. Every road accident is caused in the last resort by the invention of the internal combustion engine and by men's desire to get from one place to another.… But … the police and the courts do not weigh profound causes. They seek a specific cause for each accident―error on the part of the driver, excessive speed, drunkenness, faulty brakes, bad road surface. So it is with wars. “International anarchy” makes war possible; it does not make it certain. … Both enquiries make sense on different levels. They are complementary, they do not exclude each other.