For example this rhetorical technique is used often in the "Gay Marriage" debate. Whale Oil used it the other day when he posted a number of pictures of men and women who had "married" those of the same sex and said:
The first same-sex marriages in the state of New York have occurred. I dunno how we are going cope, it’s the end of the world as we know it.
A threat to us all?
Let's use this on another example to show what I mean. Say that blowing up Parliament, with all the politicians inside the building is a bad thing to do. I would not condone such a thing at all, and if anyone came onto this website and encouraged such an incredible act of evil in all seriousness, that I would most likely delete their comments. If I was to argue with such a person, I would say that blowing up Parliament would harm our country and our democracy, not to mention the harm done to those individuals inside the building at the time. So, there would be the immediate harm of the act itself, but then the long term consequences of such precedent for action in New Zealand.
Now, if such an action did actually come to pass, the perpetrator could use the same argument as Whale Oil did in his "Gay Marriage" thread, that the action did not have any ramifications on those not involved. All the council buildings all over the country would still be operational, all other Government buildings would still be standing, and bar a few missing politicians, the country would be much the same as it always was, ie the world didn't end, democracy wasn't destroyed, the country is still standing.
I hope I've made my point.