The major Powers did not stumble or somnambulate into the War; all of them for decades had been preparing for offensive wars against each other and each other's colonies, not to mention the disintegrating Ottoman Empire. Read Clark, MacMillan and Hastings before deciding on the "cause". Clark blames "sleepwalking", MacMillan says all of them did it but Germany more so, Hastings says Serbia did it. They are all 3 wrong, and all 3 right. Austria-Hungary bears more blame than the others but is always given a pass just as happened in 1945.