A group of scientist collabed to make the world deadlist cannon but it turned out in a other way.
The Great Leader visited the facility and decided to fund their project but only if they added enough propaganda of the Great Leader.
Propaganda added, the Great Leader founded their project, the scientist who designed the cannon was lazy and thus the cannon doesn't shoot very far but when missiles land, the land is going to be subject to great damage (Couldn't do that in the plot because I ain't authorized to change land on the testing land).
This is, the Great Leader Balistic Testing Factory ! All Heil Great Leader !