I hope he is a caring person. This is a moment of stress for you, but perhaps he has his difficulties too. Just remember this: both of you probably came abroad with next to nothing. There were probably worse time than this, and you made it through. In a family, there is no more important core value than a caring relationship. Whenever you have problems between the two of you, always come to this bottom line and work things out.
There should not be any barrier that prevents you or him from speak out what's in your mind. Not to quarrel, but to lay down all the facts and alternatives.
In my opinion, not every full time working mom can take care two young child (not every stay-home mom can do that either). If you feel you can't do it, speak out. Don't feel guilty. If he understands that, then he should be able to support you and kids while you stay home (come on, be a man!)with whatever he makes in China. If he can not support you with his current income, then he is a failure in China(sorry, that is as plain as it is) and he should come back and get a job to keep his family fed! If he doesn't understand, then you should remind him what I said earlier. His job is to keep you happy! You should demand that!
I strongly suggest you to get US citizenship before considering any moves. You see, he wants to keep all options open, and you should too. If you can trust him, you can go back with him, but give you (and your kids) a way to get back, be it good or bad.
Some people would say, man should have ambition and chase power, otherwise he is a sissy. But to you, these are meaningless. You need a man who brings home a paycheck, who puts steady hands on a toddler's bicycle, and who wipes teardrops from his wife's cheek and says, "Honey, don't worry, I will take care that."