Fred Barnes had to know his criticism of conservative Bush critics as “in some ways childish” (especially as he had it published in a conservative journal and declined to back up the insult with examples), would create at least a bit of a fuss.

Any chance Fred Barnes is doing a favor for White House staffers who do him the favor of being valued confidential sources?

Maybe not, but whenever a journalist opines against critics of a source, the possibility of a conflict of interest has to be considered.