Remember how liberals and their allies in the media reacted to all those feisty town-hall meetings about health care and environmental regulation in August? How horrible and scary they thought it was that people would loudly ask questions at a forum designed for voters to, um, ask questions?

Now we know why. Liberals prefer to protest by shouting down their rivals, as they did today at an event that Americans for Prosperity organized during the conference on global warming in Copenhagen, Denmark. Why bother debating an issue when you can just crank up the volume on the noise machine. [Mild content warning]

Sadly, the behavior of that fringe group is fairly common on the left, regardless of whether the issue is the environment, immigration or anything else.