Help: Parental right

My hu*****and is US citizen and I am green card holder sponsored by him (10 year permanent). We have 2 kids. Right now we are in trouble. He claims:

1. He will revoke my green card.
Q: can he do it? My green card is not conditional.

2. He claims that I can't take any child to visit China without his permission, but he can do it without my permission, because he is US citizen. Right now he insists on taking one child to go in 3 weeks, I am very concerned given the current situation.
Q: Is his claim true? I am not able to find relative info on web. We are in NY.

3. He claims if I dare to go for divorce, soon I will know what is the result.
Q: I don't understand what he means. He seems very confident. Will he get custody very easily due to his citizenship or due to his higher pay than me? Will I be in trouble?

Thanks very much.