I don't agree with what people are posting here... lots of times people say to work the horse more if its acting up, but to me that is not solving the actual problem, just making the horse stronger to resist longer.
IMO, you are right -- you need to deal with the respect issue. As a training point, I would teach him slowly to lower his head on command. Do this by applying down pressure on the lead and as soon as he shows any inclination to lower his head, release. Do this as often as you can w/o upsetting him... maybe only once or twice the first time and up to four times as he gets better at it. It's often a difficult thing to get a horse to do, and takes time, but it does work. I am also currently dealing with one that likes to rear when upset.
To deal with the actual rear, the trick (again, IMO only) is to catch it before she gets momentum of any kind. That means as soon as her head starts to come up, apply down and back pressure if you can, or if not turn her. It's difficult to start a rear if you through off their balance. If she does get into the rear, you can't stop it once she's started. So let her come down and calm down and try to figure out what caused it. Maybe avoid that lesson until you have the head-lowering lesson progressed further.
Rearing is, as you say and see, very dangerous. I would concentrate on this above and beyond anything else. Good luck.