I imagine many of you have enjoyed the academy award winning film titled “The Bridge on the River Kwai”. For those who may not have seen it, it’s a story of allied POW’s in a Japanese prison camp in Burma. The POW’s are being used as forced labor to complete a railroad bridge across the River Kwai. The Japanese critically needed to complete the railroad bridge for their supply route from Singapore and Bangkok to the India – Burma front to counter Lord Louis Mountbatten’s army forces operating from India.
Did you also know that the reason this railroad bridge was so critical is based on the use of sea mines?
Beginning in 1943, allied bombers, based in India, laid significant numbers of mines in the near shore waters along the coast of Thailand and the coast of Burma and south along the Malay Peninsula to Singapore. This reduced waterborne traffic flow to a trickle of smaller wooden hull ships and junks. The reduction of war materials and supplies to Japanese troops in Burma forced the flow to shift to railroad traffic, largely from Singapore overland to the Burma area, including across the River Kwai.
These sea mines also forced abandonment of a German and Japanese submarine base on the Malay Peninsula, which threatened all sea traffic through the Straits of Malacca.
Once again, sea mines provided a significant force multiplier for allied sea and land forces.