The book quickly became a media sensation for its candid, insider's critique of the Bush administration and ran as a leading story on most top news outlets days after the content became public.

[4] The book is also critical of the press corps for being too accepting of the administration's perspective on the Iraq War,[2] and of Condoleezza Rice for being "too accommodating" and overly careful about protecting her own reputation.

[1] McClellan's transformation from White House Press Secretary to prominent critic was a shock to most political observers, and his public changeover "startled Washington".

[5] The Bush administration issued a statement about the book through McClellan's successor, Press Secretary Dana Perino, who said, "Scott, we now know, is disgruntled about his experience at the White House.

[10] While McClellan's book advance was for a comparatively low $75,000, What Happened reached the number-one position on the sales chart of Amazon.com, and its printing was quadrupled to more than 300,000 copies by its publisher, PublicAffairs.