Agitprop appears to be art but is actually political propaganda. A movie that embraces an extreme political position could be called agitprop.
Agitprop, first used in 1938, is a portmanteau, or a combination of two words: agitation and propaganda. It was originally used in Soviet Russia, inspired by a Communist Party committee called the "Department for Agitation and Propaganda." The goal of this original agitprop was to spread the ideals of communism throughout the world. Agitprop theater was common in Europe and the US in the 1920s, and the term soon evolved to include political art of all kinds.