date:Dec 21, 2012
Canadian and US readers of a certain age will remember the NORAD Distant Early Warning Line that was a regular news item during the Cold War. The D.E.W. line consisted of a series of radar emplacements across the Canadian Arctic that were designed to give the military an early warning of incoming nuclear missiles from the Soviet Union.
Fortunately, the most serious threat that the D.E.W. line ever needed to deal with was Santas annual entry into North American air space every Christmas Eve.
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