The Maginot Line
France wanted Germany to be crippled, they wanted the reparation money to come through as well. they created a defensive position against Germany by creating a wall. This wall had layers much like the Wall of Berlin, a tank-proof layer, and the wall itself wasn't even a wall, on the inside was a train. The entire wall was run by electricity, the train and lights, as well as the air conditioning. The wall was something completely ahead of its time. the built this wall around the French/German border. it led them to a false sense of security, they believed that it could not be breached, but as seen in the picture below, the Germans took a picture from the French side of the border, ultimately breaching it without destroying a single thing and with little to no deaths.