Donald Trump may not be able to fire Robert Mueller. So he's doing the next best thing.

What Trump would have to do to fire Mueller
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Washington (CNN)Firing special counsel Robert Mueller would be "the beginning of the end of (Donald Trump's) presidency," predicted South Carolina Republican Sen. Lindsey Graham on CNN's "State of the Union" Sunday.

While Graham's voice is among the loudest warning Trump not to jettison the special counsel looking into Russia's interference in the 2016 election, it's far from the only one. Almost to a person, Republicans and Democrats see firing Mueller as a sort of line that once crossed can never be un-crossed -- and that could seriously jeopardize the President.
Which, of course, doesn't mean Trump won't fire Mueller. But, it does make very clear to him the stakes of doing so.
Lindsey Graham vows to protect Robert Mueller
Lindsey Graham vows to protect Robert Mueller

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Because those stakes are so high, it's possible that Trump -- as his lawyers continue to insist -- isn't even considering firing Mueller. He may well be pursuing less perilous strategy that could well reap similar rewards: Aiming to discredit Mueller and, by extension, the eventual findings of the special counsel.
    Trump's Twitter feed over the past 72 hours reeks of that attempted character assassination.
    "A total WITCH HUNT with massive conflicts of interest!," he tweeted of the special counsel investigation on Monday morning.
    That tweet followed this one on Sunday:
    "Why does the Mueller team have 13 hardened Democrats, some big Crooked Hillary supporters, and Zero Republicans? Another Dem recently added...does anyone think this is fair? And yet, there is NO COLLUSION!"
    And this one on Saturday:
    "The Mueller probe should never have been started in that there was no collusion and there was no crime. It was based on fraudulent activities and a Fake Dossier paid for by Crooked Hillary and the DNC, and improperly used in FISA COURT for surveillance of my campaign. WITCH HUNT!"
    None of this -- the tweets or the language Trump uses in them -- is new. From the outset of the special counsel's formation, Trump has publicly attacked it. He has repeatedly called it a "witch hunt" and a "total hoax" while urging the Justice Department to focus on the real problem: Hillary Clinton's use of a private email server during her time as secretary of state and the sale of a uranium company to a Russian.
    While Trump tried some nuance toward Mueller earlier this year -- he insisted his taunts of "hoax" and "witch hunt" weren't about the entire special counsel investigation but rather about the idea of collusion between his campaign and Russia -- he has abandoned that distinction since.
    And why not? After all, Trump spent his first 14 months as president servicing his political base. And there is a large element of that base who a) believes whatever Trump says b) loves the name-calling and bullying of people and institutions who they think don't serve them well and c) already thinks there is some sort of "Deep State" conspiracy designed to tear Trump down because of the threat he poses to the system.
    This is a fertile group for the message Trump is selling: No matter what Mueller finds -- even if it does involve collusion -- it must be dismissed because Mueller and his team are nothing more than a bunch of Democrats (they aren't) pursuing a political vendetta against him (there's no evidence to support this idea).
    He is seeking to turn the special counsel into just another political football. Trump's rhetoric is all designed to push his supporters to see Mueller as yet another partisan pursuing an agenda.
    That might well work! And it almost certainly is more effective than firing Mueller would be -- given the number of prominent Republicans who would condemn such a move.
    The question is whether Trump's attempt to discredit Mueller (and his findings) has any effect outside of the core Trump base. And there are two data points in the new NBC-Wall Street Journal poll that suggest it might not.
    1. Twenty-eight percent of respondents say they have a positive view of Mueller while 19% have a negative one. (The rest don't know enough about Mueller to offer an opinion.)
    2. Almost half -- 48% -- see the FBI in a positive light while 20% regard it negatively.
    Those numbers suggest demonizing the special counsel and his findings with the broader American public will be a tough task.
    Trump may not care about that, of course, believing that as long as it plays well with his base, he's doing the right thing. And, given that firing Mueller would be a massive political gamble, the attempt to sully Mueller may be Trump's best (only?) real recourse here.