Since they're putting so much spirit into this, it is very likely that they beleive that they are doing something right, and that's an opinion I happen to share. For all intents and purposes, the "winner" of this pissing match is going to be decided in a courtroom, so litigation will obviously be a weapon of choice, but don't rule out lobbying, graft, and blowjobs. I mean, we don't really have a history of settling legal matters through combat (-our- legal matters, anyway..overseas we take a different approach obviously), so the courtroom would be a logical place for it to play out in our charming faux-democratic way of doing things.
Of course, if either side said "i dont have to engage in petty litigation because I -know- i'm right!", then they'll be eaten alive and walked all over in seconds.
As long as the popular opinion is that there's nothing wrong with downloading music over the internet (and there really isn't, thats a whole 'nother can of worms that i'm sure has been belaboured to death around here), then logically there should be no legal onus against it, since the perception of the majority of the warm bodies don't have a problem with it. If the state of the music industry declines as a result (like it could get any -worse-), then we'll only have ourselves to blame, just like the music industry has only themselves to blame for not taking advantage of this new medium and gunning it down instead.