In 1942, the Japanese army had recently captured more than 200,000 Allied prisoners of war and desperately needed a new supply route to support its frontline troops in Burma. Under backbreaking conditions, POWs, along with thousands of Asian laborers, were ordered to complete a railway linking Thailand and Burma that would include the infamous “bridge on the River Kwai.” After 14 grueling months of exhaustion and malnourishment, disease, bone-deep leg ulcers, and the loss of 100,000 lives, the POWs and laborers completed the 260-mile “Death Railway.” Meanwhile, the United States military was immersed in the development of an incredible new weapon — a “smart bomb.” Early Allied attempts at bombing the railway’s narrow tracks had failed miserably, even hitting nearby Allied POW camps. Then came the Azimuth Only bomb (the AZON), so named because it could only be steered left or right, not forwards or backwards. The AZON was a standard 1,000-pound bomb with a receiver on its tail that could be guided by radio waves, a stabilizer to prevent rolling, and rudders for steering. In late 1944, a group of rescued POWs provided the first accurate information about strategic targets along the railway, and the AZON, dropped from 10,000 feet, was able to destroy the railway. It is the precursor to the high-accuracy guidable bombs recently deployed in places like Afghanistan and Iraq.