If I go to see a musician and instead, they rant about politics, I will be pissed off.
Likewise, if I go to a political debate and they whip out a guitar and play music, I will be pissed off.
I'm fine with people expressing their political views in a song (if thats what gives them inspiration and passion, then all the better) - if the musics good, I don't give a fuck what they're singing about. But giving speeches about your beliefs or doing other stupid political stunts is going too far, imo. If I you want people to listen to you rant about politics, become a politician. People are listening to you for your music, not because of your political stance.