The Fourth Horseman
One Man's Secret Mission to Wage the Great War in AmericaBook - 2006
This story has never been told before in full. And Dilger is a fascinating analog for our own troubled times. Having thrown off the tethers of obligation to family and country, he became a very dangerous man indeed: A spy, a saboteur, and a zealot to a degree that may have so embarrassed the German High Command that, after the war, they ordered his death rather than admit that he worked for them.