LitCharts assigns a color and icon to each theme in On Tyranny, which you can use to track the themes throughout the work.
The Collapse of American Democracy
Tyranny and the Consolidation of Power
Political Action and Civic Responsibility
History and Memory
Summary
Analysis
Responsible citizenship requires treating people respectfully. People living under the tyrannical governments of 20th-century Europe quickly learned to gauge whether they were safe or under threat based on their interactions with their neighbors. Plus, escaping persecution requires having friends to fall back on.
This may seem like a minor point, but maintaining normal styles of social interaction is actually crucial because it allows people to maintain power over their own lives and protect the private sphere. By refusing to let the government affect their private interactions, people can remind each other that not everybody supports the totalitarian government, which does not have all power over everything.