I can understand why this confuses non-Brits. It's really got little, if anything to do with foxes or hunting.
It's 95% to do with class and the enormous gulf between liberal urban Britain and conservative rural England.
Basically newly empowered urban Britain is still angry at the Tory voting rural areas for the Thatcher years which destroyed it's steelworks, coalmines and heavy industry. It's merely payback, it's as simple as that.
The UK is an extremely class ridden society. Everything that happens here is invariably related to class.
Foxes really have got nothing to do with it, despite what others may say.
The class thing has always interested me. A good friend of mine in college was from Twickenham. He was pretty posh- upper middle class here in U.S..-Dad from Wales and Lib Dem supoter but he hung out with a lot of "Cockneys" for lack of a better word. He explained to me how you would affect a different speech pattern depending on who you talked to.
The difference was that in the US it tends to be race and in the UK it is class that is the primary dividing line. As for Thatcher destoying heavy industry, I disagree. The industries you mentioned were on the decline before Thatcher and were not economically viable. You fail to make a profit and then you fail to exist. Same thing happened here in the US. It is very sad that people lose their jobs but you have to adapt to economic realities. I feel like singing Christy Moore's Ordinary Man right now. Best pro-labour song ever IMO.