Kill enough people and any idea can be squashed. Especially if you blame the killing on those who have the idea in the first place. Yes, killing ideas is very easy indeed. And often, it doesn't take murder to destroy an idea, just a complete lack of attention. Look at the Occupy protests, look how they drained away without fanfare, all because the media simply disallowed their ideas the oxygen of publicity. Getting rid of ideas you object to has never been easier.