On the morning of December 7, 1941, radar operators at Opana Point, Hawaii, detected an unusually large blip on their radar screen: a large group of aircraft heading for Pearl Harbor. Despite this early warning, a series of miscommunications and assumptions about the blip being friendly aircraft led to a catastrophic defensive failure.
The incoming planes were, of course, Japanese fighters, launching what would become one of the most infamous surprise attacks in military history. This incident starkly highlights the perils of underestimating the value of cutting-edge radar technology and its integration with other sensors and quick-response mechanisms.