What should I do? My boss is angry with any initiatives higher than his.
On the face of it, there is not a lot you can do. He will have to answer to someone, we all do. Sometimes challenges make teams more constructive and productive. They literally rise to the challenge.
If he struggles with that, it is not your problem, it is for him to work through. But try to understand his position.
Perhaps his pride is wounded, or maybe the person proposing the initiatives doesn’t have a good working knowledge of the department and is actually making life unnecessarily difficult for you all. You can see how that would cause frustration and anger.
This is a matter of tact and diplomacy really. Try to build an understanding with him that together you can deal with whatever initiative is proposed and produce the best result for the company. You just have to work your way round it.
But you can align with him, open a dialogue when the next initiative is proposed to which he takes exception. Talk to him about it and let him know you will try to help. Be supportive to him if you can, or sympathetic if appropriate. Perhaps even suggest the initiative may have its merits, if it does, and your opinion is sought.
If the initiative does not have merits, you could suggest to him that he could improve on the initiative, and help him do that.
Or maybe the pair of you can come up with alternative ideas and propose them.