[PeterPrinciple]

Once at the web site select:

Eyewitness: A N Korean Remembers - memoirs of a teen-age N Korean student volunteer in the US intelligence services.

[PeterPrinciple]

October 1951 - US B29 bombers carry out simulated A-bomb attacks, code-named "Operation Hudson River", on major cities in N Korea. The bombers drop dummy atomic bombs all real except for the explosives. This is intended more a psychological than tactical. It is hoped to keep N Korean leaders guessing when the real thing would come. To counter this challenge, the communists expand their air capabilities to 4,000 planes manned by Chinese, Korean and Russian pilots. On the ground, they dig 776 miles of tunnels, 3,427 miles of trenches - formidable fortifications that will withstand atomic bombs.

This is from his chapter on POWs. Anyone heard of this before?