I have ideas of what genre this would be but it could fit under multiple things, and I don't know at all which it would solely go with. The story is about three different people who have conflicting views about how to handle the next step after the fall of a government, but there is so much more to it than that. It has a subgenre of revenge, dramatic tones, parts that may seem thrilleresque, and is partly speculative fiction. I just don't know how to categorize it. Can anyone help with this?
OFF TOPIC Cultural Marxism is the marxistic background ideologia behind so called "march through the institutions". We see it and it's results every day, but mostly we don't recognise it. Marx told that there is first communistic revolution and culture changes after that. Europian communists saw in WW1 that that does not happen. Then they thought that there must be crushing of culture and it's institutions first, and communism can and will come aftter that. https://en.wikipedia.org/wiki/Frankfurt_School https://rationalwiki.org/wiki/Cultural_Marxism https://spectator.us/whats-wrong-cultural-marxism/ https://www.conservapedia.com/Cultural_Marxism You could say that it's disguised communist revolution through universities and "intellectual" elite. Social constructionism is one branch of that marxism based academic agenda & methods. They claim that reality is a social construction and there is no real reality. https://en.wikipedia.org/wiki/Social_constructionism Constructionism does have some good tools to spot anomalies. But is is used to construct main stream from different kinds of anomalies and that puts it outside scientific reasoning. It's like weighting distances, colours and temperature with a scale. It might be a good scale in it's operating range - or not - but it's mainly a way of deception when it's systematically used outside it's operating range.
Is the 'government' a real government in the real world? Or is this sci-fi/fantasy? Maybe 'alternate history?' If you start with the setting itself, you might be able to narrow down some categories. I'm not absolutely sure, as I'm not a reader of genre, as a rule ...but aren't 'thrillers' usually set in the real world? For example, a plot to bring down the present (or recent past) Cuban government, the UK's government, or the government of Moldova, or something like that, would be a 'thriller?' But a plot to bring down the government of Mars would be Sci-Fi? And a plot to bring down the rulers of Middle Earth would be Fantasy? And a plot to bring down Hitler's government (that succeeded in doing so) would be Alternate History? Pegging that aspect of your story will be a first-step towards determining genre. Then you might want to think: what's the most important thing that happens to characters in my story? What is the main thread running through the story? The revenge? A romance? Coming-of-age? Self-realisation? A new start? Those things can also help pinpoint genre. Of course also read commercial definitions of genre as well, to become familiar with the things that readers of these genres expect. If you have trouble doing this yourself, see if some beta readers can help you. (Presuming your story is finished to that extent.) Ask them if your story reminds them of any others they've read.
If this was set in the future in a made up world I would personally call it a dystopian novel. If it's set in the present day in a real world, then perhaps a political thriller, as John stated.