It would be a mistake for Trump to dump Attorney General Jeff Sessions

• The Russia probe continues to elicit over-the-top responses from President Trump.
• It would be a huge mistake if that rage leads to the firing of Attorney General Jeff Sessions.
• Replacing Sessions with Ted Cruz, Rudy Giuliani, or anyone else would not likely produce the results Trump wants.

Bastiaan Slabbers | NurPhoto | Getty Images

US Attorney General Jeff Sessions.

President Donald Trump's anger is growing so much over the continuing Russia investigation that he has started to very publicly voice a lack of confidence in Attorney General Jeff Sessions. That's even though Sessions is the man who was the first major elected leader to support Trump's presidential campaign, and his hardcore stance against illegal immigration made him a valuable political and ideological partner.

But now the president is clearly so angry that Sessions recused himself from the investigation and that he hasn't launched a similar probe into Hillary Clinton's alleged security violations, that he's publicly undermining him with regularity. And a Washington Post report says President Trump is considering replacing Sessions with either Senator Ted Cruz or former New York City Mayor Rudy Giuliani.

Here's a look at the pros and cons for all three picks:

Jeff Sessions

First off, let's not ignore what's really happening here. Anti-Trump forces in and out of Washington have successfully "gaslighted" Donald J. Trump over this Russia probe. And let's face it, this is a guy who doesn't seem too hard to gaslight in the first place.

"Gaslighting" is a term culled from the hit 1944 movie "Gaslight" starring Ingrid Bergman, Charles Boyer, and Joseph Cotton that tells the story of how an abusive husband deliberately manipulates the truth and messes with the gas-powered lighting in their home to drive her insane. Now, people use the term "gaslighting" to describe the process of deliberately making someone act irrationally.

That's what the constant stream of Democratic politicians' comments, congressional testimony, and mostly news media coverage of the alleged Russian connections to the Trump campaign have done. And it's obvious that when the probes and coverage turn to members of his own family, as it has recently to Donald Trump Jr. and the president's son-in-law Jared Kusher, he pushes back the hardest. On Tuesday, he even sarcastically tweeted about the probe now extending to his pre-teen son:

tweet

These kinds of responses may do a good job of proving President Trump is a fighter, but they don't inspire a lot of confidence that he and his administration are keeping their eye on a number of more important policy balls. President Trump needs to find some way to comment much less often about the Russia story and reverse this effective gaslighting effect it clearly has on him. Backing off his public criticism of Sessions and keeping him in the cabinet would be the best way to prove that.

Keep Sessions as the attorney general is Trump's best option.

Ted Cruz

A distant second best option would be to replace Sessions with a conservative hero like Cruz. Many conservatives are still a bit wary of President Trump and his positions, and getting a firebrand from their own camp in the cabinet could allay those fears. And coming from a deep red state like Texas with a Republican governor, the White House could be confident of not losing any Republican seats in the Senate anytime soon.

And Cruz's stance on illegal immigration, and his record of fighting relaxed immigration laws give him a lot of the same positives the Trump team sees in Sessions on that crucial issue.

But if President Trump wants a Justice Department to take the heat off the Russia investigation or shift its focus to going after Democrats like the Clintons, Cruz probably isn't the best choice. As a bona fide legal scholar, don't expect Cruz to politicize the department so quickly. He could easily end up enraging this president for all the same reasons the president is angry now.

Rudy Giuliani

We'll know the White House is in full code red mode if President Trump fires Sessions and replaces him with Giuliani, who matches the president's pugnacious personality and built a career as an ambitious prosecutor before turning to elected office. Unlike Cruz, Giuliani holds no elected office now and hasn't even been a candidate in nine years. He has less to lose and could more likely bend to the president's day-to-day whims. And if one of those whims is to fire special counsel Robert Mueller who's leading the Russia probe, all political hell will break loose.

It's not that Giuliani doesn't have the capacity to be as independent as Cruz, it just seems a lot less likely at this stage in his career and his lack of a national base to consider. Cruz probably still wants to run for president again someday — that doesn't seem to be the case with Giuliani.

Here's the bottom line: If the Trump administration wants to hold on to any credibility at all, the president needs to back off of Sessions and find another way to lash out at everyone's Russia-based obsessions.

It's not that Sessions doesn't have real political flaws. Most troubling are his positions on turning back the clock on legal marijuana laws and allowing the government to seize more private property in criminal cases. And it's also not that the constant Russia focus hasn't also damaged the Democrats' brand. But none of the negatives about Sessions are greater than the damage President Trump would do to himself and his entire political agenda if he lets him go.

It may seem like the White House has other options besides keeping Sessions on board, but it really doesn't. The only question is whether President Trump will see that before it's too late.

Commentary by Jake Novak, CNBC.com senior columnist. Follow him on Twitter @jakejakeny.

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