Kelly accused the media of protecting the former president and pressed the authors on why their reporting hadn't come out sooner.

Jake Tapper and Alex Thompson's book has already generated a national debate about whether the White House deceived the public about the president's cognitive state and how Biden's late exit from the race undermined the Democratic Party's chances of stopping Trump.

Tapper's book, co-authored by Alex Thompson, describes a president who struggled to function: "One person told us that the presidency was, at best, a five-person board with Joe Biden as chairman."