President Trump can’t stop attacking his own attorney general.

Trump started it last week in a New York Times interview where he said he would have picked someone besides Jeff Sessions for attorney general if he knew Sessions would recuse himself from the Russia investigation.

The president has only kept up the attacks since then on Twitter. Trump called his AG “beleaguered.” He said Sessions is “very weak” on investigating Hillary Clinton. He openly wondered why his cabinet official is not looking into possible collusion between Democrats and Ukraine.

But on Tuesday, Trump delivered the most devastating blow of all against the first senator to endorse him for president in an interview with The Wall Street Journal. First he said that he is “looking at” firing Sessions, then he cast doubt on why the former Alabama senator endorsed him in the Republican primary. (RELATED: Trump: ‘I’m Just Looking’ At Whether To Fire Sessions)

“I had 40,000 people. He was a senator from Alabama. I won the state by a lot, massive numbers. A lot of the states I won by massive numbers. But he was a senator, he looks at 40,000 people and he probably says, ‘What do I have to lose?’ And he endorsed me,” Trump told the Journal. “But I’m very disappointed in Jeff Sessions.”

At a Tuesday press conference shortly after the interview was published, Trump reiterated that he wished he hadn’t picked Sessions for attorney general, further cementing that the Alabaman was not in his good graces.

This displeasure is caused entirely by Sessions recusing himself from Russia, which is one of the events leading to special counsel Robert Mueller taking control of the matter. That development now represents the greatest threat to the Trump presidency.

But instead of lashing out at Mueller, Trump is singling out Sessions for all his rage — even though there’s little the attorney general can do in the matter.

And many Trump supporters, who seemingly go along with whatever the president does, are justifying Sessions removal for reasons that are remarkably similar to what were used to celebrate former FBI director James Comey’s dismissal.

They say he’s not being loyal to the president. They say he’s not investigating Hillary Clinton, which is apparently a top priority several months after the election. They also complain that he’s not competent at his job.

All of these accusations were lobbed at Comey after he was fired as well. The big difference is that Sessions is a long-time Trump supporter and is well-respected by the political right. But the same results are expected this time after getting rid of a bothersome subordinate.

And how did firing of James Comey turn out?

Well for one, there is no renewed focus on Hillary’s emails by any federal agency. Trump’s Russia woes have only increased exponentially since the former FBI director’s departure and now dominate his presidency. Instead of getting a conservative stalwart or Trump loyalist at the the helm of the FBI, Trump’s nominee for the job is another government lawyer like James Comey.

As this writer stated at the time it occurred, the Comey firing would turn out to be a catastrophe for Trump — which it has. A man who was previously busy running the FBI now spends all of his time leaking against the administration and working to bring it down. In due large part to the fallout from the firing, Mueller was appointed special counsel. (RELATED: The Predictable Catastrophe Of Firing James Comey)

None of this would have happened if Comey had stayed on. If Trump wanted him gone, he should have fired him at the start of his tenure — not several months after taking office and under dubious circumstances.

The lessons of firing Comey should serve as a notice for why Trump should lay off Sessions. Getting rid of Sessions won’t solve any of Trump’s problems. There is no chance he will get a better and more loyal choice through the Senate. The idea the next attorney general will go after Hillary over the 2016 election requires a lobotomy to believe.

There is no way Trump is going to get Rudy Giuliani or Jeanine Pirro through the Senate so they can arrest the entire Democratic Party for Benghazi. As the Comey situation shows, the replacement will turn out to be a guy who is definitely not going to implement the MAGA Twitter agenda. Sessions is the best we are going to get and he has done an effective job of promoting the Trump agenda at the DOJ.

And as Sessions supporter and Iowa Rep. Steve King said Tuesday, “Why would a high quality person take that job if they’re going to be so vulnerable?” Trump is going to have a very hard time finding a replacement after firing a loyalist for not doing the impossible.

Like the Comey firing, there will be major political fallout from dismissing Sessions — the change this time being Republicans and many Trump supporters becoming the irate party — while Democrats will only see it as a catastrophic blunder for an already troubled White House.

Is it all worth it just to get Acting Attorney General Rod Rosenstein?

The most disturbing element in this fracas is how Trump treats one of his most loyal supporters. Sessions took a major risk in endorsing Trump when the entire Republican establishment opposed his candidacy and anyone who associated with him was threatened with facing life-time opprobrium. There was little to gain and much to lose. (RELATED: Firing Sessions Would Be Terrible For Trumpism)

But Sessions believed in Trump’s message and gave him his endorsement due to his tough talk on immigration and law and order. It was not given because Trump was drawing huge crowds in a state Sessions is so popular in he ran unopposed in 2014.

Trump is deluding himself with this notion that Sessions did it out of opportunism instead of loyalty to principle, and Trump is seemingly doing it out of spite — an ominous sign to anyone who works for or supports the president.

No matter the risks you took to support Trump. No matter how effective you are at pushing the president’s job. No matter how much you helped get Trump elected. Your head will still be demanded if Trump can’t let something go.

It’s a terrible move for someone who values loyalty so much to turn on one of his most loyal supporters. It tells the world you don’t actually put much value in that quality after all.

Comey was likely fired for refusing to pledge his loyalty to Trump, but it’s hard to fault him for not doing so after seeing how Sessions is treated.

In order for Trump’s presidency to not end in total failure, he must realize the movement he ushered has to be more than a personality cult. He must offer his voters a coherent vision for the country that convinces them that he should stay in office.

There is no one better suited to help him with that task than his attorney general.

Follow Scott on Twitter and purchase his new book, “No Campus for White Men.”