I think Hitchens is agreeing with everyone here. His use of the words “lowly white hicks” is also satire. He is speaking from the point of view of the NY’er magazine.
This comment suggests otherwise:
“These are of course exactly the sort of people who do not read the New Yorker, or go in very much for the ironic and the satirical”
Ignorance is the last thing in the world Hitchens would attibute to himself. But it’s merely a lack of general experience that leads to his stereotyped thinking.