A well researched and written account of an obscure chapter of America's involvement in World War I. I read extensively on military history, and this is the only account that I have come across that explores Imperial Germany's attempt to beat the British blockade with cargo submarines. I am familiar with the World War II missions to land saboteurs in America from U-boats, but was unaware that there was an active sabotage operation being run in the States during the First War. ( )