Hi ghosty. Sorry you're having a bit of a rough time with the wee man. Feels so shite when you can't seem to get through to them, doesn't it? I know you will find a way through it though.
I think that tigermoth's post is very interesting. Though I wasn't deliberately destructive as far as I remember, I too wasn't particularly careful of my possessions as a kid- there were many incidents of dolls getting haircuts and felt tip pen makeovers, book pages being ripped, etc etc. I don't know if the two things are connected but I also tend to think of my kids' toys as theirs to do what they like with, unless something dangerous could occur by leaving them to it. If they broke something deliberately I would certainly not replace it and I would probably make it clear that I thought they'd made a mistake- because I would be genuinely angry in the heat of the moment, like you were, ghosty. I'd say something like "I feel very cross that you broke that toy. I/whoever bought it thought you would like it and take care of it, not break it on purpose." (and then witter on crossly. undermining my clear short message until I felt better!) However, I would definitely then leave them to reap the natural consequences of their own destruction, even if, like tigermoth's younger son, they didn't seem unduly bothered playing with the broken toy.
I'm guessing that the real problem here is to do with the attention-seeking aspect of this, honey? It sounds to me like your son has got the idea that the way to really, really, really ensure your and dh's full and total joint attention is to deliberately break a toy. Some children seem more prepared than others to risk even quite scary wrath from their parents with this sort of behaviour. I don't think it is always necessarily to do with lack of positive attention and doesn't sound like it is in your case, though upping the praise for anything even vaguely praiseworthy is always worth considering when you're in a rough patch with one of your kids, IMO. One of my twin sons tries to elevate this sort of behaviour to an artform- especially when told off about something. He has a strong sense of his own dignity, combined with a love of the dramatic, and seems to find it almost impossible to calmly accept situations where he feels powerless, responding by using any trick he thinks might restore him the upper hand in the power and attention stakes- laughing in our faces, using really unacceptable swear words, hitting his brother or saying with deadly seriousness "I'M NOT GOING TO LIVE WITH YOU WHEN I"M A TEENAGER!". He clearly thinks that we will certainly crumple under one of these counter-attacks and (apart from the teenager comment, which I find hilarious) I have to say he is pretty much spot on in identifying from past incidents which of our buttons to push in order to provoke a sure fire reaction. The only thing that has worked to get us out of previous horrible feeling cycles of escalating bad behaviour/telling off/worse behaviour/more telling off or punishment/even worse behaviour etc etc is by banishing our own emotion and dealing with him as matter of factly as humanly possible. This usually happened only when we'd stopped seeing his behaviour as abnormally dreadful and were therefore able to either ignore him or, if necessary, dole out justice more dispassionately- e.g. quiet but firm "time out now", lead him to room, ignore all laughter, protests, expletives. Calmly return him ro room if escape is attempted- no conversation. At end of time out a short "Ready to behave? Ok off you go." No immediate post mortem to draw attention to his crime, no further punishment for same reason. Might plan a conversation for a calm moment in the future if it's an ongoing problem.
This feels so different and so much more positive than responding in a spirit of gobsmacked rage combined with churning worry about his character and prospects (and, oh yes, I do know where he gets his dramatic streak from!) which was essentially the trap we were falling into- and I'm sure will do again next time he comes up with some behaviour we find shockingly unacceptable. I don't know if any of this will be helpful for you right now, stuck in the middle of it all, but I think and hope that when you and your dh start to accept that toy breaking is a fairly normal, if not acceptable, phase of behaviour and that, in some ways, your boy has been pretty darn clever to pick up on the fact that you (understandably) find it particularly frustrating, things will improve. Really hope it will be soon.
(btw, in case a 5 y.o perpective helps, I just asked my son what I should do if he broke a nice toy on purpose and he said, "Wait till I'm being good and then fix it for me!")