Which US president once claimed to have been 'misunderestimated'?

Bush's use of the English language in formal and public speeches has spawned several books that document the statements. A poem entitled "Make the Pie Higher", composed entirely of Bushisms, was compiled by cartoonist Richard Thompson. Various public figures and humorists, such as Jon Stewart of The Daily Show and Garry Trudeau, creator of the comic strip Doonesbury, have popularized some more famous Bushisms.

Linguist Mark Liberman of Language Log has suggested that Bush is not unusually error-prone in his speech, saying: "You can make any public figure sound like a boob, if you record everything he says and set hundreds of hostile observers to combing the transcripts for disfluencies, malapropisms, word formation errors and examples of non-standard pronunciation or usage... Which of us could stand up to a similar level of linguistic scrutiny?" Nearly a decade after George W. Bush said "misunderestimated" in a speech, Philip Hensher called the term one of his "most memorable additions to the language, and an incidentally expressive one: it may be that we rather needed a word for 'to underestimate by mistake'."