From an editorial written (during the last year of World War I) by Theodore Roosevelt:

"The President is merely the most important among a large number
of public servants. He should be supported or opposed exactly
to the degree which is warranted by his good conduct or bad
conduct, his efficiency or inefficiency in rendering loyal,
able, and disinterested service to the Nation as a whole.
Therefore it is absolutely necessary that there should be
full liberty to tell the truth about his acts, and this means
that it is exactly necessary to blame him when he does wrong
as to praise him when he does right. Any other attitude in
an American citizen is both base and servile. To announce
that there must be no criticism of the President, or that
we are to stand by the President, right or wrong, is not only
unpatriotic and servile, but is morally treasonable to the
American public. Nothing but the truth should be spoken about
him or any one else. But it is even more important to tell
the truth, pleasant or unpleasant, about him than about any
one else."

(First posted on Mark Is Cranky)