The word is dissident. You don't have activism in China, you only have (, ignoring all the regular people who just work hard and don't cause trouble) the state, its law and dissidents (who by definition are stupid people who want to go against the state and its law).

You may not be stupid if you're an "activist" in America (but you probably still are ~ engagement not activism is much better), but if people call you an "activist" in China (ha!), then you're just someone who is dumb, because you fail to understand that State and its Law.

I think I should clarify why these people are stupid. Because they ought to know that doing this is going to bring them a world of trouble, and achieve nothing, but they do so.