"I would not have declared war on Russia and France on our part, for we thereby placed ex nexu foederis first Rumania, then Italy. That was very stupid on the part of Bethmann and Jagow. Even our friends in Italy, who excuse us by saying that in the summer of 1914 we sinned not from malice, but from simplicity, cannot explain this lourde bêtise. It is indeed difficult to explain, and always will be. Ballin has assured me that the reason Bethmann insisted that we should declare war on Russia was that he thought that the Social Democrats could only be brought into it that way, expecting that “Tsarism” (detested by the whole of our Left-Wing) would affect them as a red rag affects a certain quadruped."
January 1, 1970
https://en.wikiquote.org/wiki/Theobald_von_Bethmann-Hollweg