So I've given a look over State Department policy and am unsure about exact actions that can result in revoked citizenship.
From here it seems naturalizing with intent to lose citizenship in another country is grounds for expatriation but its meaning is vague.
Let's say I somehow made my own country and declared myself president of it, and everybody in the borders at the time is granted citizenship. Do I automatically lose my U.S. citizenship? Do the other US citizens? Were they naturalized even or does that not count as naturalization and they just are citizens of the new country? Have I now forced them to choose between my stylish empire in the making or the world of American citizenry? What about getting new US citizens, what if my government had no qualms about you retaining US citizenship, are you still acting with intent to lose citizenship? This may sound wacky and unrealistic but discussing this simplified example could have some useful procedural clarifications.