NORFOLK, Va. — It goes down as one of the most deadly campaigns of World War II, yet it remains one of the least told tales.
Exactly 81 years ago, Nazi Germany launched "Operation Drumbeat," the devastating U-boat offensive in the mid-Atlantic, right here off the shores of Virginia and North Carolina.
It was January 13, 1942, the dawn of Nazi Germany's campaign to defeat America on its own shores. Eighteen of Hitler's U-boats -- or submarines -- sank nearly 500 Allied freighters and tankers along the U.S. Atlantic coast, killing around 5,000 merchant seamen and U.S. Navy sailors.
"It set the stage for a slaughter," said author Ed Offley.
In a new article published in the US Naval Institute's Naval History magazine, Offley writes that it was "a disastrous week" for the Navy.
"We just don't know the specific why or how this disaster was allowed to unfold. But we do know it unfolded," he said.
Offley writes that "the U.S. Navy had enough warships at hand to thwart the German offensive, but instead chose to do nothing" and "a bloodbath ensued."
"We wouldn't have stopped every one of them, but we sure would have stopped some of them," he explained. "And it probably would have forced the Germans to shift their tactics."
Offley said even now, eight decades later, there's an important lesson to be learned.
"Don't ignore specific, accurate intelligence," Offley advised. "They had a warning and they did nothing. And almost 5,000 sailors and 500 ships sunk. They couldn't have driven it to zero, but they probably could have cut it in half."
Additionally, 13News Now went into our archives, where we found a 1995 documentary about this often-overlooked piece of World War II history, produced by the late Terry Zahn and titled "When The War Came to America."
Click here to watch the documentary if you do not see the video below: