The man who tells this story was stationed in Germany during the Cold War. His unit was in defensive formation (a 'laager') in a muddy field one night. He did not join the card game and was out in the darkness watching NATO tanks conducting war games, using live ammo. After a few hours he realized that he had to lay a shit. He goes to a field and starts his business -- not knowing that in a few moments, this field was about to become a tank highway.