This kind of thing has happened before. In fact, these moles have even been known to encourage violence on the part of protesters so that police actually have people to arrest.
But that seems too complicated, doesn't it? Why not just use a simple show of force like the Chinese did at Tiananmen Square?
Thanks, but no tanks. We Americans like to quell political dissent with good, old fashioned subterfuge. Besides, we really don't need any more bad press these days.