On Obama's mocking comments regarding conservative's fear of refugees. That's the risk of using mockery. Used on its own, it makes ordinary people feel like you're clueless and condescending. But even if you do it right, as Obama did, the way it's reported can end up having the same effect. And that effect is exactly the opposite of what liberals would like to accomplish. So if you care about the real world, and you care about public opinion, keep the mockery to a minimum. That doesn't mean you can't fight back, and it doesn't mean you have to go easy on the fearmongers. You can do both. Just do it in a way that doesn't immediately turn off the very people you'd like to persuade.