I guess ultimately I'm indifferent; they're entitled to their opinions, and in so many cases, those opinions fuel their art. Would John Lennon be "John Lennon" without things like Revolution, or Give Peace A Chance? Neil Young and "Ohio"?
Having said that, I saw REM the week that George Bush was re-elected back in 2004, and Michael Stipe made an "impassioned" speech that was met with a smattering of boos and uncomfortable silence (and I'm in a blue state!). I saw Bruce Springsteen get booed for making a crack at Dick Cheney's expense here in Hartford. When it starts to impact the entertainment, I sort of start to bristle.
Then there's the criticism that Phil Collins took the brunt of; it's easy to talk about giving money and sharing the wealth when you're worth $250 million. I saw an interview with Sheryl Crow with Dan Rather and she's sitting in her $1M barn studio with literally 15 or 20 high-end guitars hanging on the wall preaching about being a victim.
For me it boils down to the same things as it does here in P/R. If you want to have a reasoned conversation about issues, with an open mind I'm all for artists giving a new spin on things and putting issues out there. Bruce does that well. So do David Gilmour, Genesis, and Peter Gabriel. If you're just interested in your point of view and anyone that disagrees is a unintelligent, a bigot or immoral, then I'm usually out. I never was a fan of Radiohead, but "Hail To The Thief" basically sealed the deal that they won't get a dollar of my money, nor a minute of my listening time ever again. That wasn't reasoned political discourse; that was the typical snarky, "I'm right, I'm moral, you're a stupid, inept bigot" approach to debate that I can't stand. The fact that Thom Yorke is seemingly oblivious to the rampant irony of "There There" ("Just 'cause you feel it, doesn't mean it's there") just shows a contempt that I can't get past.