It's shot day and Bart tries to evade the needle. Dr. Hibbert manages to get the job done but Bart suffers a side effect of temporary hearing loss from the shot and he takes advantage of it for all it's worth. At Springfield Elementary the annual Donkey basketball tournament is being held. During the playing of The Star Spangled Banner Bart has his shorts eaten by a donkey, leaving his bare ass exposed towards the flag. Martin snaps a picture and everyone present is outraged at this behavior.
As a result the Simpson family becomes very unpopular. They go on a cable news channel and only manage to dig themselves into a deeper hole when the host manages to twist Marge's words into saying that Springfield hates America. The negative publicity causes Mayor Quimby to change the name of the town to Liberty-Ville and they make everything patriotic. The family is arrested under violation of the "government knows best act" and they are brought to a reeducation center.
The last registered Democrat tells them how they can escape. During their musical number they escape through a tunnel but find they were on Alcatraz. They are rescued by a passing French freighter and taken to France. After being there a while they decide they miss their life in America and go back as illegal immigrants.