In reality, the leader of the group, George Dasch, turned all of them into the FBI. Hoover claimed all the credit but only when Dasch called the FBI did they have any idea German saboteurs were in the country.
German submarines landed agents in the U.S. only three times, a total ten men, of whom two were American citizens. All were quickly arrested.
In spite of many legends to the contrary, German U-boats only touched American soil three times and they didn’t stay very long. Approaching an enemy coast to land agents was extremely dangerous since the boat had to go into shallow water for one thing.
Since the only real protection a U-Boat had was going deep underwater, being in shallow water made this impossible. Officers and crewmen intensely disliked missions such as this because it put them in such danger. (Other agents were landed in Southern Ireland).
Over the years, dozens of people have told me how they had heard about German U-Boat coming ashore in the US so shop, go to the movies, have a beer, you name it. Legends and stories to the contrary, German U-Boats only touched American soil three times.
This has been confirmed to me in person by the two top U-Boat historians in the world Jak P Mallman-Showell and Dr. Timothy Mulligan.
While Jak is a British subject, he was born in Germany in 1943 and spent his early life in post-war Germany. He is a fluent German speaker. Jak’s father served in the U-Bootwaffe and was killed-in-action a few months before Jak was born. Jak has written more than 40 books on the German Ubootwaffe. Unlike most books on this subject, all of Jak’s books are meticulously researched using primary sources.
Dr. Timothy Mulligan spent his career as an archivist with the US National Archives where he specialized in captured German naval records, German military records, as well as World War Two era US military and naval records. As a fluent German speaker, Dr. Mulligan read a huge volume of these records, including original copies of German war diaries. He is the author of two works on the Ubootwaffe including: