From what you have written it sounds to me like this is newer behavior on his part. It doesn't sound like he has always been this way because this new behavior sounds foreign to you and you're not sure what to do. Hope I'm on the right track.
No matter whether it is stress or something else, it sounds like something HE needs to work on. Taking it out on you is not fair and you deserve and should demand more respect from him. In another post I believe someone said that you are too passive. I might have to agree there.
Would he be open to counseling? Not necessarily couples counseling because it sounds like HE has issues he needs to work through. Although I think it wouldn't be a bad idea for you to seek individual counseling yourself so that you can find a way to communicate to him your needs so that he will listen.
It sounds like an all around bad situation and I don't get an impression that it has always been this way. If it is stress than maybe therapy to work on stress management techniques would give him better coping skills so that he doesn't lash out at you. He needs to treat you as an equal partner and be a team player himself. I am sure it causes your children stress when you are not a unified front.
I hope this helps and that you can convince him to seek help. I am not so sure I could put up with those circumstances very long and you definitely deserve better than that.
I wish you all the best.