Polygon (1977) — animated short about war's self-sustaining horror

This 1977 Soviet science fiction film by Anatoliy Petrov touches upon war, technology and colonialism.

A military engineer, hoping to create a superweapon capable of ending war on earth, designs an advanced tank that reacts to the emotions of its targets. Things go as planned, and then they go otherwise. Its use of a unique animation technique achieves realistic, yet painterly results, and it's fun to note which western celebrities the various characters are modeled upon.