WATCH: Washington Post columnist warns of ‘extraordinary collateral damage' from Trump's FBI attacks

Longtime Washington Post columnist Dana Milbank warned Americans of the "extraordinary collateral damage" caused by President Donald Trump attacking the credibility of the FBI to attempt to distract from special counsel Robert Mueller's investigation.

"President Trump spent part of his Christmas holiday attacking the FBI and one of its top officials. This morning, President Trump was back at it again," MSNBC's Steve Kornacki noted, while guest hosting Hardball.

"Now the attacks seem to be part of a broader strategy by some on the right to undermine the FBI and the special counsel Robert Mueller," Kornacki explained.

Washington Post columnist Dana Milbrank examined the evolving defense coming from the White House.

"Originally they were saying, 'well, the president will be exonerated, Mueller won't come up with anything.' Clearly he's coming up with things," Milbank noted.

"He's got the multiple indictments and guilty pleas and based on where we see things going it's getting closer and closer to the president. So the idea now is exactly to inoculate the president so that whatever Mueller says, they will be able to say, 'well, it's a discredited investigation.'"

"The problem is the extraordinary collateral damage of telling Americans that the FBI is corrupt and tainted and not to believe in our system of law," Milbank warned.

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