Switching word definitions as an argument tactic

I've been occasionally following the discussions of Jonah Goldberg's book "Liberal Fascism," and Sam Boyd hits on a crucial point in terms of the entire analysis:

Goldberg reminds me of a friend of mine with a taste for arguments about philosophy. His secret was that he cheated. He'd argue some seemingly absurd premise but then retreat to a definition of a key word that was so different from a reasonable one that it was unrecognizable. You'd try and keep in mind his weird vocabulary, but the words maintained the force of their original meaning and it was hard to keep your argument straight. A similar thing is going on with Godlberg.

I don't have much to add to that very solid analysis, except to say that this kind of bait-and-switch, whether about words or concepts, seems to be increasingly prevalent on the right. I think this is mostly because so many conservative ideas have been implemented to such disastrous results that there's an intense period of rationalization going on. In my little area of knowledge, though, I notice it most often with talk of the surge. Since it didn't work as planned, now proponents are retreating to talking about it as focused on something totally different. It's nearly impossible to have an honest discussion about significant ideas when this is the default style of argumentation.