The Monkey Cage draws attention to McPherson and quotes one passage from his book that describes how staffers write memos for the President.
“All the memoranda I have quoted were biased. All proceeded from the personal convictions of Johnson’s advisors, which we believed he shared…. The real danger was that we would weigh it wrong. The very process of reducing a dozen position papers and committee meetings to a three-page memorandum for the President required that we exclude some arguments and data, and emphasize others. We tried to give him both sides, but our judgments colored what we wrote. Presidents are not helpless in such matters…; [they] also choose staffs on whose values they believe they can rely. But the danger of bias or omission is always there, and it is unavoidable so long as Presidents make twenty decisions a day on the basis of information they can only receive through the filter of other men’s convictions.”