Secret Nuclear Defense Plan U.S. Govt. Film #1612 Edit
This is a small excerpt from the episode Worst Episode Ever (s12e11), in which it is revealed that Springfield has been designated N.W.B. (nuclear whipping boy). Meaning that in the event of a nuclear war, all allied nations will first calibrate their missiles by bombing Springfield. The one proposing the plan, an Army officer named Steve, also shot the cameraman in order to ensure the plan stayed quiet. The video somehow got leaked out, with a pirated version also somehow getting into Jeff Albertson's possession, which was also the final film that Bart and Milhouse, showing the pirated film library to the children without Jeff Albertson's permission, showed them, due to both the tape being stuck in the VCR, and due to a police raid committed by Chief Wiggum (who had somehow learned of the illegal video stash).
During the video, a map is clearly shown that highly resembles that of Springfield Massachusetts, most notably by the large river running through the town intending to represent the Connecticut River.