In April 1918, Capt. Heinrich Nostitz, in the U-151, had been sent to the United States’ East Coast with orders to take the war to the Americans. As May ended, he had placed bombs on three ships, taking their crews prisoner in order to keep his presence a secret. Then he placed mines off the mouth of the Delaware Bay and along the Jersey Shore, finally cutting two underwater cables linking New York City to Canada and Panama.

This part of his mission completed, Nostitz decided there was no more need for secrecy. One of his prisoners, H.M.