What you're basically saying is, "sure, this and various experiences show that this kind of policing might make things worse, but hey, at least they have good intentions". Well, plenty of terrible things have been done with good intentions.

This is one of the things I really dislike about a lot of politics, I see it all too often. There's a problem, so we need to do something in the name of fixing it - doesn't matter if it helps or not, we just have to be able to say we're doing something. But maybe we should step back and look at whether there are better ways to deal with the problems.