I've got in a lot of disputes with cops over the years and somehow managed to stay out of court, in one case because the DA refused to prosecute. My name is on a watch list and I cannot get jobs in the defense complex because of it. (My day job was an electrical engineer, though I'm unemployed). I generally keep the camera out of sight anymore when cops are around.
The political fact is that by far most police in the USA work for a local municipality. Some, like in my neighborhood, work for a county. Therefore blaming "Bush" for their behavior is nonsense. They answer to a mayor who signs their paychecks. These guys put up with their behavior and the public keeps re-electing them. I guess we should blame the public if anyone.
There does seem to be a lot of this kind of crap lately all over the place. Locally, there have been a lot of cops charged with misconduct. (drunk driving, stealing, spousal abuse, rape, bribery) There seems to be several a week in the news. If they are behaving bad, it's no wonder that cameras are a threat to them. They don't want to get prosecuted and are acting to protect themselves from prosecution and litigation. Cops do act crazy when they are arresting people. I've watched them beating people up in handcuffs, spitting on them, and kicking them where it hurts. Even if you are half a mile from the scene, watching from your front porch, they have been known to arrest you for interfering. Some local judges are idiots and find people in these cases guilty. (I think judges are scared of the cops and their union that comes out around election time.) There's another guy lately in NH who was busted for having security cameras at his house that caught police acting up on his front porch. They've charged him with felonies for the taping. What I don't understand in that case is how Walmart can do it at their stores? What's the difference?
In short, I don't take pictures of cops except when they are at an event showing off their equipment, etc. I have enough trouble with vigilantes to mess with cops. I'm in complete agreement that people ought to be able to take photos of anything in public view. However, we don't live in a perfect world and it isn't worth getting shot, beat up, or sentenced to two years to get a good "shot". And yes, this does happen all over the world, not just the USA.