Surely not

There is a good bit of debate and some disagreement among constitutional scholars about the ways the president could remove Mueller if he wanted to, and the legality of such steps. But one thing is clear, it would not be as simple as firing off a termination letter, as the president did to remove FBI Director James Comey.

[...]

But could he legally squash the investigation if he wanted to?

Because Attorney General Jeff Sessions recused himself from the investigation, the decision to appoint a special counsel fell to Deputy Attorney General Rosenstein. In his order making the appointment, Rosenstein cited federal regulations issued by the attorney general in 1999, 28 C.F.R. § 600.4-600.10. The rules were drafted in the wake of the Kenneth Starr investigation of President Bill Clinton.

According to those regulations, a special counsel “may be disciplined or removed from office only by the personal action of the Attorney General” (or in this case, the acting attorney general). And Rosenstein can’t just do it on a whim, either. Because Attorney General Jeff Sessions recused himself from the investigation, the decision to appoint a special counsel fell to Deputy Attorney General Rosenstein. In his order making the appointment, Rosenstein cited federal regulations issued by the attorney general in 1999, 28 C.F.R. § 600.4-600.10. The rules were drafted in the wake of the Kenneth Starr investigation of President Bill Clinton. According to those regulations, a special counsel “may be disciplined or removed from office only by the personal action of the Attorney General” (or in this case, the acting attorney general). And Rosenstein can’t just do it on a whim, either.

  Factcheck

Surely Rosenstein, who was shamed after writing a note covering Trump's big ass for firing Comey, wouldn't want to relive that debacle by firing Mueller. But what if Trump fired Rosenstein? Who would have the authority then?

“It’s certainly theoretically possible that the attorney general could fire him, but that’s the only person who has authority to fire him,” Rosenstein said. “And in fact, the chain of command for the special counsel is only directly to the attorney general, in this case the acting attorney general.”

Could Jeff Sessions rescind his recusal? He's in enough trouble as it is in this whole thing. I can't imagine he's got the balls to get himself in any further. (In fact, I wouldn't be surprised if he's already secretly turned cooperative with Mueller in the hopes of staying out of jail.)

If he wanted to, wrote Jack Goldsmith, a Harvard Law School professor and co-founder of Lawfare, Trump could then fire Rosenstein. In that case, the authority over Mueller would fall to the associate attorney general. In theory — and ignoring the political consequences of doing so — Trump could keep firing people until he got someone to follow through on an order to fire Mueller.

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There’s yet another route the president could take, Neal Katyal, a professor of national security law at Georgetown University, wrote in a piece for the Washington Post on May 19: “Trump could order the special-counsel regulations repealed and then fire Mueller himself.”

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" If Trump tries to blow through the regulation and fire Mueller himself, would DOJ or Mueller accept the termination or instead challenge and litigate the purported removal?” Goldsmith wrote. “That litigation would be … interesting.”

To say the least.

You think there wouldn't be riots outside the White House if they fired Mueller?  I think it's gone too far now that these indictments have been handed down and Papadopoulos took a plea deal.  They may spew and fume, but I have to think they all know now that Mueller has real and damning evidence against them, and their inclinations will be to do whatever it takes to mitigate damages, shift blame and stay out of jail. 

...but hey, do what you want...you will anyway.