The president also told reporters he was likely to revoke the clearance of Bruce Ohr, a Department of Justice official who is linked to a dossier on Trump's campaign and Russian Federation compiled by former British spy Christopher Steele.
Former CIA directors and another half dozen of America's most senior spies have issued an unprecedented condemnation of President Donald Trump, after his decision to blacklist their colleague John Brennan.
The bipartisan group of United States intelligence figures, which included Robert Gates, George Tenet, David Petraeus, James Clapper and Leon Panetta, lashed out at the president in a scathing letter released late on Thursday.
When Maddow asked what Brennan feared Trump could do in his desperation, he suggested that the president might launch an overseas military adventure to distract the nation - a classic "wag the dog" scenario. And that's been followed by another statement signed by 60 other former intelligence officials critical of the president's move.
Trump says the official, Bruce Ohr, is a "disgrace".
The signees include six former CIA directors, five former deputy directors and former Director of National Intelligence James Clapper. Gates and Panetta also served as secretaries of defense.
The extreme action of revoking security clearances is one more instance of Donald Trump undertaking measures that no other president has done, leaving legal analysts in question about whether the action is actually within his authority.
The president may have connected the dots for Robert Mueller, showing that he had started a security clearance-revoking rampage, not because he wants to protect classified information, but because he wants to silence, and punish his critics, those tied to the Russian Federation investigation in particular.
Brennan said he believes Trump stripped his security clearance for political reasons and wants to "silence others who might dare to challenge him". Many people don't even know who he is, and now he's a bigger voice, and that's okay with me, because I like taking on voices like that. "So I think it's something that had to be done".
According to CNN's Jake Tapper, by stripping Brennan of his security clearance, and by compiling a list of officials he'd like to move against, Trump may have entrapped himself.
Trump said that in addition to Brennan, the security clearances of nine other former officials are under review. "As part of this review, I'm evaluating action with respect to the following individuals - James Clapper, James Comey, Michael Hayden, Sally Yates, Susan Rice, Andrew McCabe, Peter Strzok, Lisa Page and Bruce Ohr". For him to be in the Justice Department and doing what he did, that is a disgrace.
Trump added that Special Counsel Robert Mueller is also "highly conflicted". Last year, in a speech at the University of Texas, he pushed back against Trump's assault on the news media as "the enemy of the American people".