The article I've just now cited for 'dooced' goes on to mention the term 'barking moonbat'. Is someone pulling my leg here?

Naturally, we assumed Pronk's site would reveal him to be the sort of strident ideologue that bloggers call a "barking moonbat," ...

Allegedly coined by Heinlein in 1947.

I read through the Wiki article . . . but I still don't get a clear meaning. Does it basically just mean "crazy person"?

I read the article to mean that it is an American phrase used by politicians to refer to those who hold differing views.