Characters
How the hell do I know why there were Nazis? I don't know how the can opener works!
— Mickey's father
Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The answer places a vast historical question beside a small everyday mystery. By admitting that even a can opener defeats him, the speaker makes his inability to explain something much larger sound unsurprising. The drastic change in scale supplies the comic effect.
Context reviewed